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~~TABLE~~As filed OFwith ~~CONTENTS~~the Securities and Exchange Commission on August 18, 2025

AsRegistration No. ~~filed with the Securities and Exchange Commission on April 21, 2022~~333-[●]

~~Registration No. 333-~~ UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

~~Washington~~WASHINGTON, D.C. 20549

FORM S-1

REGISTRATION ~~STATEMENT~~ STATEMENT UNDERTHE SECURITIES ACT OF 1933

UNDER

THE SECURITIES ACT OF 1933

ADVENT TECHNOLOGIES HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware		6770	~~6770~~	83-0982969		~~83-0982969~~
(State or other jurisdiction of incorporation or organization)		(Primary Standard Industrial Classification Code Number)	~~(Primary Standard Industrial Classification Code Number)~~	(I.R.S. EmployerIdentification Number)		~~(I.R.S. Employer Identification No.)~~

~~200~~5637 La ~~Clarendon~~Ribera ~~Street~~ St.

~~Boston~~Suite A, MALivermore, ~~02116~~ CA 94550

(~~857~~925) ~~264-7035~~ 455-9400

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

~~Vassilios Gregoriou~~Gary HermanChief Executive Officer

~~Chief~~5637 La ~~Executive~~Ribera ~~Officer~~ St., Suite A

~~200 Clarendon Street~~Livermore, CA 94550

~~Boston, MA 02116~~(925) 455-9400

(857) 264-7035

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to: Tom Rosedale, Esq. Nutter, McClennen & Fish, LLP 155 Seaport Boulevard Boston, Massachusetts 02110 (617) 439-2000 Chad Friend, Esq. Anthony, Linder & Cacomanolis, PLLC 1700 Palm Beach Lakes Blvd., Suite 820 West Palm Beach, FL 33401 (855) 654-1929

~~Katherine~~Approximate date J.of ~~Blair,~~commencement ~~Esq~~of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective.

~~Manatt,~~If any ~~Phelps~~of &the ~~Phillips,~~securities ~~LLP~~being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ☒

~~2049~~If this ~~Century~~Form ~~Park~~is ~~East~~filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, ~~Suite~~please ~~1700~~check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

~~Los~~If this ~~Angeles~~Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, CAcheck ~~90067~~the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(~~310~~d) ~~312-4000~~under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

~~Approximate~~Table ~~date~~ of ~~commencement of proposed sale to the public: From time to time after this Registration Statement becomes effective.~~Contents

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box: ☒

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer ~~ ~~ ☐ ~~ ~~ Accelerated filer ~~ ~~ ☐ Non-accelerated filer ~~ ~~ ☒ ~~ ~~ Smaller reporting company ~~ ~~ ☒ ~~ ~~ Emerging growth company ~~ ☒~~☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for ~~complying~~ comply with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of ~~the~~ Securities Act. ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until ~~this~~the registration statement shall become effective on such date as the Commission, acting pursuant to ~~said~~such Section 8(a), may determine.

~~TABLE~~Table OFof ~~CONTENTS~~Contents

~~Information~~The information ~~contained~~in ~~herein~~this prospectus is ~~subject~~not tocomplete ~~completion~~and ormay ~~amendment.~~be ~~A registration statement relating to these securities has been filed with the SEC~~changed. These securities may not be sold ~~nor~~until ~~may~~the ~~offers~~registration tostatement filed ~~buy~~with ~~be accepted prior to~~ the ~~time~~Securities ~~the~~and ~~registration~~Exchange ~~statement~~Commission ~~becomes~~is effective. This prospectus ~~shall~~is not ~~constitute~~ an offer to sell orthese ~~the~~securities ~~solicitation~~and ofit anis ~~offer~~not soliciting offers to buy ~~nor shall there be any sale of~~ these securities in any ~~jurisdiction~~state inwhere ~~which~~the ~~such~~ offer, ~~solicitation~~ or sale ~~would~~is benot ~~unlawful~~permitted.

PRELIMINARY PROSPECTUS SUBJECT TO COMPLETION, DATED ~~April~~AUGUST 2118, ~~2022~~2025

~~PRELIMINARY~~Up to ~~PROSPECTUS~~987,036 Shares of Common Stock

~~ADVENT~~This ~~TECHNOLOGIES~~prospectus ~~HOLDINGS~~relates to the offer and resale of an aggregate of up to 987,036 ~~INC~~shares of our common stock, $0.0001 par value per share, by Hudson Global Ventures, LLC (“Hudson Global” or the “Selling Stockholder”). The shares included in this prospectus consist of shares of common stock that we have issued or that we may, in our discretion, elect to issue and sell to Hudson Global, from time to time after the date of this prospectus and the date of the satisfaction of the conditions to the Selling Stockholder’s purchase obligations (the “Commencement Date”) as set forth in the equity purchase agreement we entered into with Hudson Global on August 14, 2025 (the “Purchase Agreement”). Pursuant to the Purchase Agreement, Hudson Global has committed to purchase from us, at our direction, up to $52,000,000 of our common stock, subject to the terms and conditions specified in the Purchase Agreement. See the section titled “Hudson Global Transaction” for a description of the Purchase Agreement and the section titled “Selling Stockholder” for additional information regarding Hudson Global.

10We are not selling any shares of common stock being offered by this prospectus and will not receive any of the proceeds from the sale of such shares by Hudson Global. However,~~152~~ we may receive up to $52,~~865~~000,000 ~~Shares~~in aggregate gross proceeds from sales of ~~Common~~our ~~Stock~~common stock to Hudson Global that we may, in our discretion, elect to make, from time to time after the date of this prospectus, pursuant to the Purchase Agreement.

~~This prospectus relates to the offer and sale,~~Hudson ~~from~~Global ~~time~~may tosell ~~time, by the selling securityholders named in this prospectus (the “Selling Securityholders”),~~ or ~~any~~otherwise ofdispose ~~their permitted transferees,~~ of upthe ~~to an aggregate of 10,152,865~~ shares of ~~our~~ common stock, ~~consisting~~included ofin ~~(i)~~this ~~5,124,846~~prospectus ~~shares issued~~in toa ~~F.E.R.~~number ~~fischer~~of ~~Edelstahlrohre~~different ~~GmbH~~ways onand ~~August 31,~~at ~~2021~~varying prices. ~~pursuant~~See to the ~~Share~~section ~~Purchase~~titled ~~Agreement,~~“Plan ~~dated as~~ of ~~June 25,~~Distribution” ~~2021,~~for ~~and~~more ~~(ii) 5,028,019~~information ~~shares~~about ~~held~~how byHudson ~~other~~Global ~~Selling~~may ~~Securityholders.~~sell ~~This~~or ~~prospectus also covers any additional~~otherwise ~~securities~~dispose ~~that may become issuable by reason~~ of ~~share~~the ~~splits,~~common ~~share~~stock ~~dividends~~being oroffered ~~other~~in ~~similar~~this ~~transactions~~prospectus. WeHudson ~~will~~Global ~~not~~is ~~receive~~an ~~any~~“underwriter” ~~proceeds~~within ~~from~~ the ~~sale~~meaning of ~~shares~~Section 2(a)(11) of ~~common~~the ~~stock~~Securities byAct ~~the~~of ~~Selling~~1933, ~~Securityholders~~as ~~pursuant~~amended to(the ~~this~~“Securities ~~prospectus~~Act”).

We will pay the expenses of registering these shares, but all selling and other expenses incurred by the Selling Securityholders in disposing of the securities, associated with the sale of securities pursuant to this prospectus will be paid by the Selling Securityholders.

Our registration of the securities covered by this prospectus does not mean that the Selling Securityholders will issue, offer or sell, as applicable, any of the securities. The Selling Securityholders and any of their permitted transferees may offer and sell the securities covered by this prospectus in a number of different ways and at varying prices. Additional information on the Selling Securityholders, and the times and manner in which they may offer and sell the securities under this prospectus, is provided under “Selling Securityholders” and “Plan of Distribution” in this prospectus.

You should read this prospectus and any prospectus supplement or amendment carefully before you invest in our securities.

Our common stock and warrants are listed on Nasdaq under the symbols “ADN” and “ADNWW”, respectively. On ~~April~~August 2014, ~~2022~~ 2025, the closing price of our common stock was $23.2168 per share and the closing price of our warrants was $0.~~4289~~0246 per share.

~~We are an “emerging growth company” and a~~Investing ~~“smaller~~in ~~reporting~~our ~~company”~~securities asinvolves ~~such~~risks ~~terms~~that are ~~defined~~described ~~under~~in the ~~federal~~“Risk ~~securities~~Factors” ~~laws~~section ~~and,~~beginning ason ~~such,~~page ~~are~~12 ~~subject~~of ~~to certain reduced public company reporting requirements~~this prospectus.

~~Investing~~Neither the inSecurities ~~our~~and ~~securities involves~~Exchange ~~risks~~Commission ~~that~~nor ~~are~~any ~~described~~state insecurities ~~the~~commission ~~“Risk~~has ~~Factors”~~approved ~~section~~or ~~beginning~~disapproved onof ~~page~~these 13securities ofor determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

~~Neither the SEC nor any state~~The ~~securities~~date ~~commission has approved or disapproved~~ of ~~the securities to be issued under~~ this prospectus ~~or determined if this prospectus~~ is , ~~truthful or complete. Any representation to the contrary is a criminal offense.~~ 2025

~~The~~Table ~~date~~ of ~~this prospectus is , 2022.~~Contents

TABLE OF CONTENTS

TABLE OF CONTENTS

		Page
PROSPECTUS SUMMARY		1
RISK FACTORS		12
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS		35
HUDSON GLOBAL TRANSACTION		37
USE OF PROCEEDS		41
PLAN OF DISTRIBUTION		43
DIVIDEND POLICY		45
CAPITALIZATION		46
DILUTION		47
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS		48
BUSINESS		68
MANAGEMENT		83
EXECUTIVE COMPENSATION		89
CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS		100
PRINCIPAL SHAREHOLDERS		101
DESCRIPTION OF SECURITIES		102
PLAN OF DISTRIBUTION		108
LEGAL MATTERS		110
EXPERTS		111
WHERE YOU CAN FIND MORE INFORMATION		112
FINANCIAL STATEMENTS		F-1

ABOUT THIS PROSPECTUS			1
SELECTED DEFINITIONS			2
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS			4
SUMMARY OF THE PROSPECTUS			6
RISK FACTORS			13
USE OF PROCEEDS			28
MARKET INFORMATION FOR SECURITIES AND DIVIDEND POLICY			29
UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS			30
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS			36
BUSINESS			50
MANAGEMENT			60
EXECUTIVE COMPENSATION			66
DESCRIPTION OF SECURITIES			72
SECURITIES ACT RESTRICTIONS ON RESALE OF SECURITIES			79
PRINCIPAL STOCKHOLDERS			81
SELLING SECURITYHOLDERS			83
CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS			85
UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS			89
PLAN OF DISTRIBUTION			94
LEGAL MATTERS			98
EXPERTS			98
CHANGE IN AUDITOR			98
WHERE YOU CAN FIND MORE INFORMATION			99
INDEX TO CONSOLIDATED FINANCIAL STATEMENTS			F-1

~~TABLE~~Table OFof ~~CONTENTS~~Contents

~~ABOUT THIS~~ PROSPECTUS SUMMARY

This summary highlights information contained elsewhere in this prospectus. isThis ~~part~~summary ofdoes anot ~~registration~~contain ~~statement~~all onof ~~Form~~the ~~S-1~~information that you weshould ~~filed~~consider ~~with~~before ~~the~~deciding ~~SEC~~to ~~using~~invest ain ~~“shelf”~~our ~~registration process~~securities. ~~Under~~You should carefully read this ~~shelf~~entire ~~registration~~prospectus ~~process~~before making an investment decision, including the ~~Selling~~information ~~Securityholders~~presented ~~and~~under ~~their~~the ~~permitted~~headings ~~transferees~~“Risk ~~may,~~Factors” ~~from~~and ~~time~~“Cautionary Statement toRegarding ~~time,~~Forward-Looking ~~issue,~~Statements” ~~offer~~in ~~and~~this ~~sell,~~prospectus asand ~~applicable,~~the ~~any~~historical ~~combination~~financial ofstatements and the notes ~~securities~~thereto ~~described~~included in this prospectus. You should pay special attention to the information contained under the caption titled “Risk Factors” in ~~one~~this orprospectus ~~more~~before ~~offerings.~~deciding to buy our securities.

~~The~~Unless otherwise ~~Selling~~indicated ~~Securityholders~~by ~~may use~~ the ~~shelf~~context, ~~registration~~reference ~~statement to~~in ~~sell~~this upprospectus to an“Advent”, ~~aggregate~~“we,” ~~of 10~~“us,~~152,865 shares~~” of “our ~~common stock. The Selling Securityholders and their permitted transferees may use the shelf registration statement to sell such securities from time to time through any means described in the~~,” ~~section entitled~~ “~~Plan of Distribution.~~Company” ~~More specific terms of any securities that the Selling Securityholders~~ and ~~their~~similar ~~permitted~~references ~~transferees~~are ~~offer~~to ~~and sell may be provided in a prospectus supplement that describes, among other things,~~ the ~~specific~~combined ~~amounts~~business ~~and prices~~ of ~~the~~Advent ~~common~~Technologies ~~stock~~Holdings, ~~being~~Inc. ~~offered~~ and ~~the~~its ~~terms of the offering~~consolidated subsidiaries.

~~A prospectus supplement or post-effective amendment may also add,~~Our update or change information included in this prospectus. Any statement contained in this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in such prospectus supplement or post-effective amendment modifies or supersedes such statement. Any statement so modified will be deemed to constitute a part of this prospectus only as so modified, and any statement so superseded will be deemed not to constitute a part of this prospectus. You should rely only on the information contained in this prospectus, any applicable prospectus supplement, post-effective amendment or any related free writing prospectus. See “Where You Can Find More Information.” Company

Neither we nor the Selling Securityholders have authorized anyone to provide any information or to make any representations other than those contained in this prospectus, any accompanying prospectus supplement or any free writing prospectus we have prepared. We and the Selling Securityholders take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the securities offered hereby and only under circumstances and in jurisdictions where it is lawful to do so. No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus. This prospectus is not an offer to sell securities, and it is not soliciting an offer to buy securities, in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus or any prospectus supplement is accurate only as of the date on the front of those documents only, regardless of the time of delivery of this prospectus or any applicable prospectus supplement, or any sale of a security. Our business, financial condition, results of operations and prospects may have changed since those dates. Overview

~~For~~We are ~~investors~~an ~~outside~~advanced materials and technology development company operating in the ~~U.S.~~fuel cell and hydrogen technology space, ~~neither~~including weliquid hydrogen ~~nor~~carriers such as methanol. We are a world-leading company in the ~~Selling Securityholders~~development ~~have~~of ~~done~~HT-PEM ~~anything~~(High ~~that~~Temperature ~~would~~Proton ~~permit~~Exchange ~~this~~Membrane) technology ~~offering~~(with orapproximately ~~possession~~150 patents issued, pending, or ~~distribution~~licensed ofworldwide). ~~this~~The ~~prospectus~~HT-PEM infuel ~~any~~cell ~~jurisdiction~~technology ~~where~~enables ~~action~~off-grid power ~~for~~systems ~~that~~to ~~purpose~~produce isclean ~~required~~power from various green fuels (hydrogen, ~~other~~methanol, ~~than~~bio and e-Methanol, and renewable natural gas) and to function with higher efficiency at extreme ambient temperatures and in ~~the~~general Uextreme environmental conditions (humidity, air pollution).S. Advent’s ~~Persons~~main ~~outside~~operations focus on developing and manufacturing the ~~U.S.~~Membrane ~~who~~Electrode ~~come~~Assembly ~~into~~(MEA) and the fuel cell stack, which ~~possession~~is the core electrochemical element and the most critical component of ~~this~~the ~~prospectus~~fuel ~~must~~cell. ~~inform~~The ~~themselves~~MEA ~~about~~and the fuel cell stack largely determines lifetime, power density, efficiency, and ~~observe~~overall ~~any~~cost ~~restrictions~~of ~~relating~~installation ~~to,~~and operation for all applications. Advent is working with global market-leading OEMs with the ~~offering~~goal of ~~our~~bringing ~~securities~~to ~~and~~ the ~~distribution~~market complete fuel cell systems for a range of ~~this~~applications ~~prospectus~~in ~~outside~~the stationary power markets (backup, off-grid, and portable power) and the ~~U.S.~~heavy-duty mobility markets (automotive, aviation, marine).

~~This prospectus contains summaries of certain provisions contained~~Our inmission ~~some of the documents described herein, but reference~~ is ~~made~~ to ~~the~~bring ~~actual~~fuel ~~documents~~cells ~~for~~that ~~complete~~have ~~information.~~a ~~All~~lower ofTotal ~~the~~Cost ~~summaries are qualified in their entirety by the actual documents. Copies~~ of ~~some~~Ownership of(TCO) ~~the documents referred~~ to ~~herein have~~market ~~been~~when ~~filed,~~compared ~~will~~to bediesel ~~filed~~generators orand ~~will~~internal combustion beengines. ~~incorporated~~Our bygoal ~~reference~~is ~~as exhibits~~ to ~~the~~become ~~registration~~a ~~statement~~leading provider of ~~which~~HT-PEM ~~this~~fuel ~~prospectus~~cell ~~is a part~~systems, stacks and ~~you~~HT-PEM-based ~~may~~membrane ~~obtain~~electrode assemblies ~~copies of those documents as described below under~~ (“~~Where~~MEA” ~~You~~or ~~Can Find More Information.~~“MEAs”).

A large portion of our current revenue is derived from Joint Development Agreements (JDAs) and Technology Assessment Agreements (TAAs) with world-leading OEMs for the development of joint products. The ultimate goal is for OEMs to bring fuel cell systems specialized for each application to the market. These systems will be branded by the OEMs and function with Advent-inside technology (the Advent MEA and/or the Advent fuel cell stack). The Company also has extensive know-how and IP in the development of complete fuel cell systems that it intends to license out to OEMs and Tier 1s through technology license agreements. While fuel cell stack sales and associated revenue is expected to provide the majority of our income in the near future, the MEA innovation is expected to facilitate future strategic partnerships between Tier 1 suppliers and us and original equipment manufacturers (“OEMs”) as these downstream manufacturers develop their own white-labeled HT-PEM products. We have had early success in forging such strategic partnerships, as with the case of Airbus for the aerospace sector and previously with Siemens Energy for the maritime industry. The US Army development contracts for human portable power fuel cells also fall under this category.

~~TABLE~~Table OFof ~~CONTENTS~~Contents

~~SELECTED~~Our headquarters ~~DEFINITIONS~~are in Livermore, California, and we have MEA and fuel cell stack product development facilities in Livermore, California and Patras, Greece. Our investment priorities are increasing MEA performance and meeting the milestones of the Joint Development Agreements we have with various customers and partners including Airbus, Hyundai Motors and the US Army. Our business priorities are to expand our network of strategic OEM relationships in the Automotive and large-scale Stationary power markets.

~~Unless the context otherwise requires, in this prospectus,~~Please ~~references~~see ~~to “Advent”,~~ the ~~“Company”,~~section ~~“us”,~~entitled “weBusiness”, ~~“our”~~on ~~and~~page ~~any related terms prior to the closing of the Business Combination are intended to mean Advent Technologies Inc.~~68, afor ~~Delaware~~more ~~corporation, and its consolidated subsidiaries and after the closing of the Business Combination are intended to mean Advent Technologies Holdings, Inc~~information.~~, a Delaware corporation, and its consolidated subsidiaries.~~

~~“AMCI” means AMCI~~Our ~~Acquisition Corp., a Delaware corporation, which was renamed “Advent Technologies Holdings, Inc.” in connection with the Closing.~~Background

Advent Technologies Holdings, Inc., a Delaware corporation (the “Company”), was originally named AMCI ~~IPO”~~Acquisition ~~means~~Corp. (“AMCI’s”), and was established as a special purpose acquisition company, which completed its initial public offering in November 2018. AMCI was incorporated for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses, and, prior to the Business Combination, the Company was a “shell company” as defined under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), because it had no operations and nominal assets consisting almost entirely of cash.

“Business ~~Combination”~~ ~~means the Merger and the other transactions contemplated by the Merger Agreement.~~Strengths

~~“Closing”~~Highly Differentiated ~~means~~Technology: We believe that for the ~~closing~~reasons ofexplained above, HT-PEM is a highly differentiated technology that provides significant competitive advantages to Advent and our partners. HT-PEM technology is a new and promising technology when compared to LT-PEM (Low Temperature Proton Exchange Membrane), that was developed for the ~~Business~~last ~~Combination~~50 years and may have plateaued in terms of expected technology breakthroughs needed to overcome thermal control and environmental limitations.

~~“Combined~~Experienced management ~~Entity”~~team ~~means~~with ~~AMCI~~a proven track record: We were ~~after~~founded ~~giving~~and ~~effect~~managed toby ~~the~~world-class ~~Business~~electrochemists, ~~Combination~~material scientists, ~~including~~and ~~Advent~~fuel cell specialists with significant industry and ~~any~~manufacturing expertise. ~~other~~We ~~direct~~have orreceived ~~indirect~~numerous ~~subsidiaries~~R&D funds from the US DoE and the European Union and are considered a pioneer with years of experience ~~AMCI~~in clean energy technology innovation. The team that we have recruited to bring innovation to the fuel cell industry is highly experienced and has a long pedigree in R&D and world-class manufacturing. Our team has been developing MEA components since 2006 and is led by Dr. Emory De Castro (CTO).

~~“common~~Strategic Partnership ~~stock”~~with ~~means~~US ~~the common~~DoE ~~stock,~~and ~~par~~Los ~~value~~Alamos ~~$0.0001~~National ~~per~~Laboratories: In ~~share~~addition, ofwe ~~Advent~~initiated ~~Technologies~~in ~~Holdings,~~2021 ~~Inc.~~a ~~following~~Cooperative ~~the~~Research ~~Business~~and ~~Combination;~~Development ~~such~~Agreement ~~common~~(CRADA) ~~stock~~under ~~was~~the ~~previously~~U.S. ~~designated~~Department ~~Class A~~of ~~common~~Energy ~~stock~~(“DoE”) umbrella ofto ~~AMCI,~~commercialize ~~and~~next-generation ~~which~~MEAs ~~includes~~and ~~any~~ultra-low ~~shares~~platinum ofcatalyst ~~Class B~~solutions ~~common~~developed ~~stock of~~by ~~AMCI~~the ~~that~~National ~~was~~Laboratories ~~converted~~at ~~into~~Los Alamos, ~~Class A~~Brookhaven, ~~common~~and ~~stock~~NREL, in ~~connection~~the ~~with~~U.S. ~~the~~We ~~Closing~~were ~~pursuant~~selected toas the ~~amended~~scale-up and ~~restated~~commercialization ~~certification~~partner of ~~AMCI~~the ~~prior~~DoE toand are working closely with the ~~Business~~highly-skilled ~~Combination~~R&D teams of top U.S. government laboratories.

~~“DGCL”~~MEA IP ~~means~~and Technology: We firmly believe in the ~~Delaware~~transformative ~~General~~potential ~~Corporation~~of ~~Law~~the Advent MEA to redefine the global fuel cell market, asenabling ~~amended~~applications that were previously unattainable with conventional fuel cell materials. Our objective is to enhance the MEA’s capabilities when operating at 160°C to 180°C for more than 20,000 hours, delivering a higher power density that will result in a simpler, more cost-effective system with superior performance in terms of weight, power, lifetime, total cost of ownership, and infrastructure investment. As we continue to strengthen our collaborations with some of the world’s largest OEMs and Tier 1 Manufacturers, our aim is to capitalize on the growing momentum and demand for our HT-PEM technology.

“Effective Time” means the effective time of the Merger in accordance with the Merger Agreement.

“Exchange Act” means Securities Exchange Act of 1934, as amended.

“EY” means Ernst & Young (Hellas) Certified Auditors Accountants S.A., Advent’s independent auditor.

“Marcum” means Marcum LLP, AMCI’s independent auditor.

“Merger” means the merger of Merger Sub with and into Advent, with Advent continuing as the surviving corporation and as a wholly-owned subsidiary of AMCI, in accordance with the terms of the Merger Agreement.

“Merger Agreement” means the Agreement and Plan of Merger, dated October 12, 2020, and amended on October 19, 2020 and amended again on December 31, 2020, by and among AMCI, Merger Sub, the Purchaser Representative, Advent Technologies Inc. and the Seller Representative.

“Merger Sub” means AMCI Merger Sub Corp., a newly-formed Delaware corporation and wholly-owned subsidiary of AMCI.

“PIPE Investment” refers to the sale of shares of newly issued Class A common stock to the PIPE Investors in a private placement that was consummated simultaneously with the closing of the Business Combination.

“PIPE Investors” means the investors in the PIPE Investment.

“PIPE Subscription Agreements” means the subscription agreements, dated December 22, 2020, by and among AMCI and the investors named therein relating to the PIPE Investment.

“Placement Warrants” means 3,940,278 warrants to purchase shares of Class A common stock issued to Sponsor in the Private Placement, which, after the Business Combination, entitles the holder thereof to purchase one share of common stock for $11.50 per share.

“Private Placement” means the private placement consummated simultaneously with the AMCI IPO in which AMCI issued to the Sponsor the Placement Warrants.

“Public Warrants” means warrants underlying the Units issued in the AMCI IPO, which after the Business Combination, entitles the holder thereof to purchase one share of common stock for $11.50 per share.

“Purchaser Representative” means Sponsor in the capacity as the Purchaser Representative under the Merger Agreement.

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~~“SEC” means the U.S.~~Products ~~Securities~~ and ~~Exchange Commission.~~Services

~~“Securities~~We derive ~~Act”~~revenue ~~means~~from the ~~Securities~~ ~~Act~~following ~~of 1933, as amended.~~sources:

1. Engineering and License Fees: In the mobility sector (e.g., heavy-duty automotive, mining equipment, marine, aerospace), we are entering into Joint Development Agreements (“~~Seller~~JDAs”) ~~Representative~~(as in the case of Hyundai and Airbus) to develop joint solutions for specific sectors. We plan to enter into Technology License Agreements (“TLAs” ~~means~~) ~~Vassilios~~to ~~Gregoriou~~allow in3rd party Tier 1 manufacturers or world-leading companies to market the ~~capacity~~licensed asAdvent technology in exchange for a license fee. We intend to be a provider of MEAs and core technology via licensing rather than producing complete fuel cells for the ~~Seller~~mobility ~~Representative~~industry. ~~under~~Revenue from JDAs may include engineering fees during the ~~Merger~~1-3 ~~Agreement~~year initial development cycle (“JDA fees”), MEA sales, and ongoing licensing fees.

~~“Sponsor”~~2. ~~means~~MEA ~~AMCI~~Sales: ~~Sponsor LLC~~We develop and manufacture the critical component of the fuel cell, the MEA. The operation of the MEA is key to the functionality and characteristics of a fuel cell system. In addition to our fuel cell system offerings, our MEA is a discrete product offering to third-party manufacturers. MEA sales are expected to be a rapidly growing market as more fuel cells are deployed globally by third parties, especially in the mobility space.

~~“Units”~~3. ~~means~~Fuel ~~Units~~Cell ~~issued~~ Systems and Stacks: As our JDAs mature and move to manufacturing partnerships we expect to derive revenue from fuel cell systems and stacks for portable and stationary power generation applications range from 20W to MWs. These fuel cells have applications in the ~~AMCI~~data ~~IPO~~center, ~~including~~commercial ~~any~~and ~~overallotment~~industrial ~~securities~~backup, ~~acquired~~telecom bytower ~~AMCI’s~~and ~~underwriters~~other critical infrastructure (e.g., ~~consisting~~5G, of4G) ~~one~~power, ~~share~~defense of(and ~~Class A~~other ~~common~~portable ~~stock~~power applications), and ~~one~~heavy-duty ~~Public~~mobility ~~Warrant~~(automotive trucks, aviation, marine) power markets.

~~“Warrants” means any of the~~Addressable ~~Placement Warrants, the Public Warrants and the Working Capital Warrants.~~Markets

~~“Working~~Based on ~~Capital~~the ~~Warrants” means~~several ~~400~~critical advantages offered by our HT-PEM technology over batteries and LT-PEM technology,~~000~~ ~~warrants~~we ~~issued~~expect to ~~the~~be ~~Sponsor~~highly competitive in ~~connection~~numerous ~~with~~applications. ~~its~~Our ~~election~~HT-PEM tofuel ~~convert~~cells ~~loans~~and ~~made~~MEAs byare itwell-suited to ~~AMCI~~off-grid ~~prior~~power, toportable ~~the~~power ~~closing~~applications, ofcombined ~~AMCI’s~~heat and ~~initial~~power, ~~business~~and ~~combination~~mobility in(e.g., ~~accordance~~heavy-duty ~~with~~automotive, ~~the~~aviation, ~~AMCI~~mining ~~IPO~~equipment, ~~prospectus~~marine, atand aUAV). ~~price~~Our ofgoal ~~$1.00~~is ~~per~~to partner with Tier ~~warrant~~1 suppliers and OEMs in these new markets, ~~which~~focusing ~~warrants~~on ~~are~~fuel ~~identical~~cell totechnology development, licensing, and the ~~Placement~~mass ~~Warrants~~production of the next-generation MEAs. Please see the section entitled “Business” on page 68, for more information.

Business Strategy

Our growth strategy is focused on targeting the following four sectors:

●

The stationary off-grid market is expected to be a growing market.

●

The large-scale fuel cell systems market (power generation, data centers and power to gas).

●

The human-portable defense, surveillance, energy infrastructure, and leisure market based on our innovative Honey Badger products.

●

The development of next-generation MEA and fuel cell solutions for the mobility market.

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~~CAUTIONARY~~Our approach ~~NOTE~~extends ~~REGARDING~~beyond ~~FORWARD~~direct sales; we actively supply our membrane electrode assemblies (MEAs) to other fuel cell manufacturers, and we intend to supply core technology through technology transfer agreements to OEMs. This serves as a cornerstone for our expansion plans, focusing on scaling up through the licensing of our technology. Central to our strategy for future growth is the emphasis on licensing agreements with large-~~LOOKING~~scale ~~STATEMENTS~~manufacturers possessing market access and robust service, support, and capital expenditure capabilities. Through partnerships with Tier1s and OEMs, we empower our collaborators to innovate and commercialize fuel cell systems powered by Advent’s proprietary technology on a significant scale. Our collaborators actively manage the entire value chain, including sales, marketing, and after-sales service. Until these partnerships mature and reach the mass manufacturing stage, we derive revenues from major partners through Joint Development Agreements, which are pivotal in financing the early stages of market-specific product development.

~~The~~As our ~~statements~~business ~~contained~~ramps inup ~~this~~to ~~prospectus~~mass production, we plan to pursue a revenue model that ~~are~~includes ~~not~~fuel ~~purely historical~~cell ~~are~~system ~~forward~~sales, MEA sales, and hardware-~~looking~~technology licensing ~~statements~~fees. Our ~~forward-looking~~customer ~~statements~~relationship ~~include,~~is ~~but~~split ~~are~~into ~~not~~two ~~limited~~phases: 1) partner with OEMs to, ~~statements~~co-develop ~~regarding~~customized ~~our~~fuel orcell systems based on our ~~management~~expertise ~~team’s~~in ~~expectations,~~MEAs ~~hopes,~~and ~~beliefs,~~HT-PEM ~~intentions~~fuel orcell ~~strategies~~systems. ~~regarding~~During the ~~future.~~product Indevelopment ~~addition~~phase, ~~any~~ ~~statements~~we ~~that~~earn ~~refer~~engineering ~~to projections~~fees, ~~forecasts~~and or2) ~~other~~once ~~characterizations~~the industry ofand ~~future~~application-specific ~~events~~fuel orcell ~~circumstances~~system are qualified, ~~including~~we ~~any~~intend ~~underlying~~to ~~assumptions,~~license ~~are~~the ~~forward-looking~~hardware ~~statements.~~design ~~The~~to ~~words~~OEMs ~~“anticipate,”~~or ~~“believe,”~~Tier1s ~~“continue,”~~for ~~“could,”~~large-scale ~~“estimate,”~~manufacturing ~~“expect,”~~in ~~“intends,”~~exchange ~~“may,”~~for ~~“might,”~~license ~~“plan,”~~fees. ~~“possible,”~~In ~~“potential~~addition,” ~~“predict,”~~we ~~“project,”~~intend ~~“should,”~~to ~~“would”~~manufacture and ~~similar~~sell ~~expressions~~proprietary ~~may~~MEAs ~~identify~~directly ~~forward-looking~~to ~~statements,~~OEMs ~~but~~and ~~the~~Tier1s. We ~~absence~~expect ofhigh-margin ~~these~~licensing ~~words~~fees ~~does~~and ~~not~~MEA ~~mean~~sales ~~that~~to become a ~~statement~~ islarger ~~not~~component ~~forward-looking~~of our revenue mix over time (vs. ~~Forward-looking~~direct ~~statements~~fuel incell ~~this~~system sales) ~~prospectus~~as ~~may~~our ~~include,~~customers ~~for~~scale ~~example,~~to ~~statements~~mass ~~about:~~manufacturing of fuel cells and other products.

•We intend ~~our~~to ~~ability~~focus future production activities in the USA and potentially in Western Macedonia, Greece, upon IPCEI funding approval. We have significant capacity in place when it comes to ~~maintain~~MEA manufacturing. Regarding fuel cell manufacturing, we expect to license the ~~listing~~technology to oflarge-scale ~~our~~manufacturers ~~shares~~and ofselectively ~~common~~manufacture ~~stock~~it (for defense and ~~warrants~~other onpromising ~~Nasdaq;~~markets directly).

•Specific Product ~~our~~Offerings ~~ability~~Under ~~to raise financing in the future;~~Development

•A. ~~our~~Advent ~~success in retaining or recruiting officers, key employees or directors;~~MEA:

•The Advent ~~factors~~MEA ~~relating~~(also called the “Ion Pair MEA”) allows HT-PEM fuel cells to ~~our~~operate ~~business,~~between ~~operations~~80°C and ~~financial~~240°C ~~performance,~~with ~~including~~an optimal temperature of 160°C. The implications of high-temperature operation are:

○1. ~~our~~It ~~ability~~is toideal ~~control~~for eFuel-based fuel cells (e-Methanol). The HT-PEM fuel cell can work with reformate gas, impure hydrogen, and eFuels, so there is no need for new infrastructure. The existing fossil liquid fuel infrastructure, with minimal changes but without the ~~costs~~carbon ~~associated~~footprint, can be used for shipping, powering off-grid generators, and solving the hardest mobility electrification applications where batteries are simply not enough. (Our systems require a single-stage methanol or alternative eFuel gas reformer, typically yielding approximately 70% hydrogen and 1-2% carbon monoxide, with ~~our~~the ~~operations;~~remaining balance being carbon dioxide. In contrast, competing systems necessitate costly multistage reformers and palladium-based purifiers to maintain carbon monoxide levels below 10-15 ppm, a requirement for the operation of LT PEM.

○2. It enables highly-efficient thermal management at the system level, making our ~~ability~~fuel cells ideal for aviation and heavy-duty automotive. Airplanes, big trucks, excavators, and most heavy-duty applications face significant thermal management challenges. Efficient heat rejection is not possible, especially in areas of the world that keep getting hotter every year. From India to ~~grow~~the Arizona desert, an HT-PEM fuel cell is the superior technology. By operating optimally at 160 °C, the Advent MEA is the first technology to beat the US Department of Energy heat rejection target by reaching a ΔQ/T level of 1.03 at a hot 50 °C, far below the 2025 goal of 1.45 set at only 40 °C, a target the current LT PEM technology can not reach. By running the MEA hot, you can keep the fuel cell engine cool and ~~manage~~use ~~growth~~smaller ~~profitably;~~radiators for less drag.

○ our reliance on complex machinery for our operations and production;

○ the market’s willingness to adopt our technology;

○ our ability to maintain relationships with customers;

○ the potential impact of product recalls;

○ our ability to compete within our industry;

○ increases in costs, disruption of supply or shortage of raw materials;

○ risks associated with strategic alliances or acquisitions, including the acquisition of SerEnergy A/S, a Danish stock corporation (“SerEnergy”) and fischer eco solutions GmbH, a German limited liability company (“FES”), former wholly-owned subsidiaries of F.E.R. fischer Edelstahlrohre GmbH, completed on August 31, 2021;

○ the impact of unfavorable changes in U.S. and international regulations;

○ the availability of and our ability to meet the terms and conditions for government grants and economic incentives; and

○ our ability to protect our intellectual property rights.

• market conditions and global and economic factors beyond our control, including the potential adverse effects of the ongoing global coronavirus (COVID-19) pandemic on capital markets, general economic conditions, unemployment and our liquidity, operations and personnel;

• volatility of our stock price and potential share dilution;

• future exchange and interest rates; and

• other factors detailed herein under the section entitled “Risk Factors.”

These forward-looking statements are based on information available as of the date of this prospectus, and current expectations, forecasts and assumptions, and involve a number of judgments, risks and uncertainties. Important factors could cause actual results to differ materially from those indicated or implied by forward-looking statements such as those contained in documents we have filed with the U.S. Securities and Exchange Commission. Accordingly, forward-looking statements should not be relied upon as representing our views as of any subsequent date, and we do not undertake any obligation to update forward-looking statements to reflect events or circumstances after the date they were made, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

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As3. aIt ~~result~~enables simple design as the balance of plant is much simpler (due to nO-water management issues). The Advent MEA does not use water as the conducting medium. It is based on a ~~number~~unique ofproprietary ~~known~~chemistry developed by Advent and ~~unknown~~our ~~risks~~collaborators. “No water needed” means that the HT-PEM fuel cell system’s balance of plant and ~~uncertainties~~, ~~our~~thus, ~~actual~~the ~~results~~design, ortesting, ~~performance~~and ~~may~~manufacturing beis ~~materially~~much ~~different~~simpler. ~~from~~Thus ~~those~~the ~~expressed~~HT-PEM fuel cell can operate at extreme humidity high or ~~implied~~low, byextreme ~~these~~climates ~~forward~~(temperature (-~~looking~~20 ~~statements.~~°C ~~For~~to a55 ~~discussion~~°C)), ofor ~~the~~air ~~risks~~quality ~~involved~~conditions in(pollution, ~~our~~dust). ~~business~~All ~~and~~these ~~investing~~factors inhave ~~our~~minimal ~~common~~or ~~stock,~~no ~~see~~effect on the ~~section~~ ~~entitled~~HT-PEM ~~“Risk~~fuel ~~Factors~~cell performance, but they can be life-ending for a typical LT-PEM system.”

~~Should~~On August ~~one~~6, or2025, ~~more~~the ofCompany ~~these~~entered ~~risks~~into ora ~~uncertainties~~new ~~materialize,~~enhanced ~~or should~~license ~~any~~agreement ofwith TRIAD National Security for the ~~underlying~~Ion ~~assumptions~~Pair ~~prove~~technology ~~incorrect,~~originally developed ~~actual~~at ~~results~~Los ~~may~~Alamos ~~vary~~National inLaboratory. ~~material~~In ~~respects~~the ~~from~~new ~~those~~enhanced ~~expressed~~license, orAdvent ~~implied~~acquired byexclusivity ~~these~~to ~~forward-looking~~the ~~statements.~~technology ~~You~~in ~~should~~the ~~not~~marine, aviation, ~~place~~and ~~undue~~portable ~~reliance~~power onfields ~~these~~while ~~forward~~retaining its non-~~looking~~exclusive ~~statements~~rights in all other fields.

The license covers the following exclusive fields of use:

●

Marine: Vessel propulsion, marine vessel auxiliary power, and dockside vessel support to provide electrical or thermal, direct or indirect (e.g., charging battery bank) power for propulsion or support of auxiliary operations such as lighting, navigation, communication, climate control, refrigeration, galley operations, hotel loads or standby power for crew and passenger accommodations.

●

Aviation: Fuel cell power systems for aircraft propulsion, auxiliary power units (APU), and ground power units (GPU). Auxiliary servicing functions includes cabin lighting, avionics testing, galley operations, and air conditioning. Fuel cell power systems as GPUs on the airport premise grounds would support aircraft maintenance, pre-flight preparation, and auxiliary servicing functions such as cabin lighting, avionics testing, air conditioning, engine start-up, and battery charging.

●

Human Portable Power: Fuel cell power units having a fuel-free system weight of 160 lbs. (72 Kg.) or less, providing electric power for defense, emergency, or expeditionary operations, remote sensing and field instrumentation, charging of personal electronic devices or mission-critical equipment, or off-grid backup power in austere environments and designed to be carried, worn, or transported by an individual without the aid of a vehicle.

Advent Fuel Cell Stack

Following the discontinued operations in Denmark and the Serene product line, we have focused our efforts on the development of the next-generation fuel cell stack:

The goal of this effort, which commenced in 2024 Q3 and will be ongoing, is to develop the next generation of HT-PEM fuel cells based on the Advent MEA. Performance-wise, our goal is to double the power density of the fuel cell stacks in the near future vs. the previous Serene product line (that was not based on Advent MEA) and also double the lifetime. These developments can result in a total capex reduction of approximately 3x vs. previous Serene systems, thus enabling a very attractive total cost of ownership model for almost all business cases in stationary and marine power. A further improvement target of 3x vs. previous MEAs resulting from improved Advent MEA and fuel cell stack performance can bring significant competitive advantages in the most challenging markets of Aerospace and Automotive.

The Advent Fuel Cell Stack will be in the range of 7kW-10kW multiples of which can be placed in cabinets for higher power, such as 100kW to 150 kW; however, longer term Advent is designing a 50kW block, thus enabling multi-MW installations by deploying parallel cabinets. Other features under development are associated with Advent’s proprietary edge-cooling technology, no methanol-water mix and metal bipolar plates use.

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~~SUMMARY~~C. OFHoney ~~THE PROSPECTUS~~Badger

~~This~~The Reformed ~~summary~~Methanol ~~highlights~~Wearable ~~selected~~Fuel ~~information~~Cell Power System, or “Honey Badger” is an offering marketed by our subsidiary Advent Technologies ~~from~~LLC. ~~this~~On ~~prospectus~~June 7, 2021, the US DoD, through the U.S. Army DEVCOM Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance, and ~~does~~Reconnaissance ~~not~~(C5ISR) ~~contain~~Center, ~~all~~with funding through the Project Manager Integrated Visual Augmentation System (PM IVAS), has entered into a contract with us to complete the MIL-STD certification of the ~~information~~cutting ~~that~~edge “Honey Badger”. “Honey Badger” is ~~important~~placed toon ~~you~~a insoldier-worn ~~making~~plate ancarrier ~~investment~~and ~~decision~~provides on-the-move battery charging in the field. ~~This~~It ~~summary~~has isbeen ~~qualified~~selected by the US DoD’s National Defense Center for Energy and Environment (NDCEE) to take part in its ~~entirety~~2021 bydemonstration/validation program and is the ~~more~~only ~~detailed~~fuel ~~information~~cell ~~included~~to take part in this ~~prospectus~~program. ~~Before~~The ~~making~~NDCEE is a US DoD program that addresses high-priority environmental, safety, ~~your~~occupational ~~investment~~health, ~~decision~~and ~~with~~energy ~~respect~~technological tochallenges ~~our~~that ~~securities~~are demonstrated and validated at active installations for military application. The product is offered at 50W and 100W power versions, ~~you~~and ~~should~~both ~~carefully~~are ~~read~~in the testing and certification stages. Its core technology has completed successful field trials in Army Expeditionary Warrior Experiments and high-altitude tests in California’s Sierra Nevada. Advent Technologies LLC’s “Honey Badger 50” (the 50W power version) fuel cell is the only fuel cell that is part of this ~~entire~~program ~~prospectus~~that supports the U.S. Army’s goal of having a technology-enabled force by 2028. On August 4, ~~including~~2022, we announced the ~~information~~launch ~~under~~of ~~“Risk~~our ~~Factors~~HB50 power system,” ~~“Management~~a compact portable fuel cell system and quiet power supply for use in off-grid field applications such as military and rescue operations. The launch of Advent’s ~~Discussion~~portable power system coincided with the Company’s fulfillment of its first shipment order from the U.S. Department of Defense. The HB50 power system can be fueled by biodegradable methanol, allowing near-silent generation of up to 50W of continuous power with clean emissions. Designed for covert operations, HB50 can easily power radio and ~~Analysis~~satellite communications gear, remote fixed and mobile surveillance systems, laptop computers, and more general battery charging needs. HB50 is a unique technology that can save 65% of ~~Financial~~weight ~~Condition~~versus batteries over a typical 72-hour mission. The weight savings benefit increases further for longer missions. In September and ~~Results~~December 2023, contracts totaling $2.2 million and $2.8 million, respectively, were signed with the U.S. Department of ~~Operations~~Defense. These contracts focus on integrating the Ion Pair MEA technology into HB50 and enhancing specific components/manufacturing processes. The objective is to facilitate the shift from low-prototype volume to small manufacturing volume. Advent and the US DoD plan to strengthen their collaboration by concentrating on the improved HB50 fuel cell system’s manufacturing process,” aiming to achieve high-volume production capacity. Multiple applications of the HB50 are expected in the ~~“Unaudited~~future ~~Pro~~in ~~Forma~~sectors ~~Condensed~~such ~~Combined~~as ~~Financial~~robotics, ~~Information”~~agriculture, drones, emergency operations, and consumer uses. HB50’s unique design allows it to be used in soldier-worn configurations or operated inside a portable backpack or vehicle while charging batteries and powering soldier systems, while its thermal features allow it to operate within an ambient temperature range of -20°C to +55°C. Aside from its optimized compatibility with the ~~financial~~Integrated ~~statements~~Visual ~~included~~Augmentation ~~elsewhere~~System (“IVAS”), HB50 can also power devices such as high-frequency radios, such as the model 117G and B-GAN and StarLink terminals. HB50’s durability allows it to be easily deployed in ~~this~~challenging ~~prospectus~~conditions and climates while supporting mission mobility for three to seven days without the need to re-supply. Since Honey Badger’s fuel cell technology can run on hydrogen or liquid fuels, the system can operate at a fraction of the weight of traditional military-grade batteries to meet the U.S. Department of Defense’s continuously evolving needs for ‘on-the-go’ electronics needs. As military adoption and use of IVAS equipment continue to evolve, highly portable lightweight power solutions like Honey Badger and HB50 will become a mission-critical necessity.

~~The Company~~Intellectual Property

~~Advent is an advanced materials and technology development company~~Our ~~operating~~intellectual inproperty ~~the~~portfolio ~~fuel~~covers, ~~cell~~among ~~and~~other ~~hydrogen~~things: ~~technology~~membranes, ~~space.~~electrodes, ~~Advent develops~~MEAs, ~~manufactures~~ and ~~assembles~~systems exploiting the ~~critical~~unique ~~components~~operating characteristics ~~that~~of ~~determine~~its ~~the~~materials. ~~performance~~In ofgeneral, ~~hydrogen~~our ~~fuel~~employees ~~cells~~are ~~and~~party ~~other~~to ~~energy~~agreements ~~systems.~~providing ~~Advent’s~~that ~~core~~all ~~product~~inventions, ~~offering~~whether ispatented ~~the~~or ~~Membrane~~not, ~~Electrode~~made ~~Assembly~~or ~~(MEA)~~conceived atwhile ~~the~~being ~~center~~an ~~of the fuel cell. The~~ Advent ~~MEA~~employee, which ~~derives~~are ~~its~~related ~~key~~to ~~benefits~~or result from ~~the~~work ~~properties~~or ofresearch ~~Advent’s~~that ~~engineered~~the ~~membrane~~Company ~~technology~~performs, will ~~enables~~remain aour ~~more~~sole ~~robust, longer-lasting~~ and ~~ultimately~~exclusive ~~lower-cost fuel cell product~~property.

ToWe have ~~date~~been issued, ~~Advent’s~~acquired, ~~principal~~licensed, ~~operations~~or ~~have~~applied ~~been~~for ~~developing~~approximately ~~and manufacturing~~150 ~~MEAs,~~international and ~~designing~~United ~~fuel~~States ~~cell~~patents, ~~stacks~~with ~~and~~a ~~complete~~concentration in ~~fuel~~membranes, ~~cell~~electrodes, ~~systems~~and MEAs, ~~for~~which asupport ~~range~~its ofproduct ~~customers~~offerings. inLeveraging ~~the~~our ~~stationary~~membrane ~~power,~~and ~~portable~~electrode ~~power~~technologies, ~~automotive,~~we ~~aviation,~~also have ~~energy~~the ~~storage~~intellectual ~~and~~property ~~sensor~~for ~~markets.~~lightweight ~~Advent~~stacks ~~has~~made ~~its~~through ~~headquarters~~advances in ~~Boston~~bipolar plate materials, ~~Massachusetts~~ inwhich ~~the~~support Uwater-cooled systems.~~S.,~~ This results in a ~~product~~simpler ~~development~~and ~~function~~more incompact ~~Boston,~~balance-of-plant ~~Massachusetts~~design. Our own investments in ~~the~~developing ~~U.S.,~~leading ~~and~~next-generation afuel ~~MEA~~cell technology ~~assembly~~are supported by being able to leverage the research and ~~production~~development ~~facility~~efforts inof ~~Patras,~~its ~~Greece.~~strategic partners.

The majority of Advent’s current revenues derive predominantly from the sale of MEAs, but also from the sale of membranes and electrodes for specific applications in the iron flow battery and cellphone markets respectively. Whilst MEA sales and associated revenues are expected to provide the majority of Advent’s future income, both of these markets remain commercially viable and have the potential to generate material future revenues based on Advent’s existing customers. Advent has also secured grant funding for a range of projects from research agencies and other organizations in the U.S. and Greece and expects to continue to be eligible for grant funding based on its product development activities over the foreseeable future.

Advent plans to scale up both its U.S. and Greece operations in order to handle substantial increases in MEA production volumes, and enable it to execute a range of product development programs that are designed to increase Advent’s overall product suite, improve the performance of its core MEA product and optimize its production operations to improve unit production costs.

Background

Advent Technologies Holdings, Inc., a Delaware corporation (the “Company”), was originally named AMCI Acquisition Corp. (“AMCI”), and was established as a special purpose acquisition company, which completed its initial public offering in November 2018. AMCI was incorporated for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses, and, prior to the Business Combination, the Company was a “shell company” as defined under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), because it had no operations and nominal assets consisting almost entirely of cash.

On February 4, 2021, AMCI consummated the Business Combination pursuant to the terms of the Merger Agreement, including the merger of AMCI Merger Sub Corp., a newly-formed Delaware corporation and wholly-owned subsidiary of AMCI (“Merger Sub”) with and into Advent Technologies Inc., with Advent Technologies Inc. continuing as the surviving corporation and as a wholly-owned subsidiary of AMCI, in accordance with the terms of the Agreement and Plan of Merger, dated October 12, 2020 , and amended on October 19, 2020 and amended again on December 31, 2020, by and among AMCI, Merger Sub, AMCI Sponsor LLC in its capacity as the Purchaser Representative, Advent Technologies Inc. and Vassilios Gregoriou in the capacity as the Seller Representative.

In connection with the Closing, AMCI changed its name to “Advent Technologies Holdings, Inc.” and each outstanding share of Class A common stock, including any shares of Class B common stock that were converted into

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~~shares~~Our rights ofto ~~Class A~~commercialize ~~common~~the ~~stock,~~next-generation ~~were~~HT-PEM ~~redesignated~~materials astechnology ~~common~~from ~~stock.~~the WeDoE ~~continued~~L’Innovator Program also includes rights to ~~the~~a ~~listing~~portfolio of patents supporting this advanced technology. We were selected through a highly competitive bidding process by virtue of our ~~common~~management ~~stock~~team’s ~~and~~track ~~public~~record ~~warrants~~in ontaking ~~the~~laboratory ~~Nasdaq~~inventions ~~Stock~~and ~~Market~~processes ~~under~~through ~~the~~to ~~symbols~~a ~~“ADN”~~fully scaled and ~~“ADNWW”,~~manufactured ~~respectively~~product. We ~~Prior~~expect tothat this technology will reduce production costs of its MEAs significantly through a 3-fold increase in power output per unit area of the ~~Closing,~~membrane ~~our~~and ~~Class A~~will ~~common~~provide ~~stock,~~a ~~public~~longer ~~warrants~~operating lifetime and ~~units~~a ~~were~~wider ~~listed~~temperature onoperating ~~the~~range ~~Nasdaq~~as ~~Stock~~well ~~Market~~as substantially lower ~~under~~platinum content. We expect these advantages will enable us to reduce the ~~symbols~~cost ~~“AMCI”,~~to ~~“AMCIW”~~end-users of fuel cells and ~~“AMCIU”~~encourage wider market adoption.

The rights of holders of our common stock and warrants are governed by our second amended and restated certificate of incorporation, our amended and restated bylaws and the Delaware General Corporation Law (the “DGCL”), and in the case of the warrants, the Warrant Agreement, dated November 15, 2018 by and between AMCI and Continental Stock Transfer & Trust Company, as warrant agent. See the sections entitled “Description of Securities” and “Selling Securityholders.”Competition

~~Emerging~~The market ~~Growth~~for ~~Company~~alternative fuel and energy storage systems is still in the early stages of growth and is characterized by well-established battery and LT-PEM products. We believe the principal competitive factors in the markets in which it operates include, but are not limited to, the size, weight, lifetime, durability, and total cost of ownership of these systems to the end-user. We believe that our HT-PEM technology competes with these other technologies across a number of new and existing applications in the alternative energy fuel market, especially in the realm of fuel flexibility and heat management. We believe the total addressable market opportunity could be over $72 billion by the year 2030. Please see the section entitled “Business” on page 68, for more information.

~~We are an “emerging growth company,” as defined in Section 2(a) of~~Employees the Securities Act of 1933, as amended (the “Securities Act”), as modified by the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and ~~comply~~Human ~~with~~Capital the requirements that apply to non-emerging growth companies but any such an election to opt out is irrevocable. Advent elected not to opt out of such extended transition period which means that when a standard is issued or revised and it has different application dates for public or private companies, Advent, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard, until such time Advent is no longer considered to be an emerging growth company. At times, Advent may elect to early adopt a new or revised standard. See Note 2 of the accompanying audited financial statements for the recent accounting pronouncements adopted and the recent accounting pronouncements not yet adopted for the years ending December 31, 2020 and 2019.Resources

InOur employees ~~addition,~~are ~~Advent~~critical ~~intends~~ to ~~rely~~our ~~on the other exemptions and reduced reporting requirements provided by the JOBS Act~~success. ~~Subject~~As toof ~~certain conditions set forth in the JOBS Act~~December 31, if2024, aswe anhad ~~emerging~~approximately ~~growth~~26 ~~company,~~employees ~~Advent~~and ~~intends~~5 topart-time ~~rely~~contractors. ~~on such exemptions, Advent is not required to, among other things: (a)~~We ~~provide~~occasionally anrely ~~auditor’s attestation report~~ on ~~Advent’s~~additional ~~system~~independent ofcontractors ~~internal control over financial reporting pursuant~~ to ~~Section~~support ~~404(b)~~our ofoperations. ~~the~~None ~~Sarbanes-Oxley Act; (b) provide all~~ of ~~the~~our ~~compensation~~employees ~~disclosure~~are ~~that~~represented ~~may be required of non-emerging growth public companies under the Dodd-Frank Wall Street Reform and Consumer Protection Act; (c) comply with any requirement that may be adopted~~ by ~~the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or~~ a ~~supplement~~ tolabor the auditor’s report providing additional information about the audit and the financial statements (auditor discussion and analysis); and (d) disclose certain executive compensation-related items such as the correlation betweenorganization ~~executive~~or ~~compensation~~are ~~and~~a ~~performance~~party ~~and comparisons of the Chief Executive Officer’s compensation~~ to ~~median~~any ~~employee~~collective ~~compensation~~bargaining arrangement.

~~Advent will remain an emerging growth company under the JOBS Act~~We ~~until~~strive ~~the~~to ~~earliest~~create ~~of (~~a) ~~the~~collaborative ~~last~~environment ~~day~~where ofour ~~Advent’s~~colleagues ~~first~~feel ~~fiscal~~respected ~~year~~and ~~following~~valued. ~~the~~We ~~fifth~~provide ~~anniversary~~our ofemployees ~~its~~with ~~initial public offering~~competitive compensation, ~~(b)~~opportunities ~~the~~for ~~last~~equity ~~date of Advent’s fiscal year in which Advent has total annual gross revenue of at least $1.1 billion~~ownership, ~~(c)~~and ~~the date on which Advent is deemed to be~~ a ~~“large~~robust ~~accelerated~~employment ~~filer”~~package, ~~under~~including ~~the~~health ~~rules~~care, ofretirement ~~the~~benefits, ~~SEC~~and ~~with~~paid time ~~at least $700~~off.~~0 million~~ ofIn ~~outstanding~~addition, ~~securities~~we ~~held~~regularly byinteract ~~non-affiliates~~with orour ~~(d)~~employees ~~the~~to ~~date~~gauge onemployee ~~which~~satisfaction ~~Advent~~and ~~has~~identify ~~issued~~focus ~~more than $1~~areas.~~0 billion in non-convertible debt securities during the previous three years.~~

~~Risk~~At Advent, ~~Factors~~we champion the belief that individual uniqueness enhances greatness. We uphold equal opportunities for all employees. Through rigorous protocols, we continuously work to identify and eradicate any form of harassment within our organization, fostering a fair and respectful workplace. We prioritize the value and respect of our employees, unequivocally condemning violence, discrimination, or harassment. Employees are encouraged to address any questions or concerns they may have regarding their employment or benefits with our Human Resources department. We honor and accommodate the physical or mental limitations of qualified employees with disabilities, enabling them to fulfill their job responsibilities. Furthermore, our compensation structure is determined by factors such as position, education, and experience.

Our ~~business is subject to numerous risks and uncertainties,~~ ~~including~~Risks ~~those highlighted in the section titled “Risk Factors”, which represent challenges that we face in connection with the successful implementation of our strategy~~ and growth of our business. The occurrence of one or more of the events or circumstances described in that section, alone or in combination with other events or circumstances, may have a material adverse effect on our business, cash flows, financial condition and results of operations.Challenges

An investment in our securities involves a high degree of risk. You should carefully consider the risks summarized below. These risks are discussed more fully in the “Risk Factors” section immediately following this Prospectus Summary. These risks include, but are not limited to, the following:

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~~These~~Risks Related ~~risk~~to ~~factors~~Our ~~include,~~Operations ~~but~~and ~~are not limited to, the following:~~Business

•● We have identified material weaknesses in our system of internal controls pursuant to Section 404 of the Sarbanes-Oxley Act of 2002. If not remediated, these material weaknesses could result in material misstatements in our consolidated financial statements. We may be unable to ~~adequately~~develop, ~~control~~implement ~~the~~and ~~costs~~maintain ~~associated~~appropriate ~~with~~controls ~~our~~in ~~operations~~future periods.

•● WeIf ~~may~~we ~~need~~fail to ~~raise~~maintain ~~additional~~an ~~funds~~effective ~~and~~system ~~these~~of ~~funds~~internal controls, we may not be ~~available~~able to usaccurately ~~when~~report weour ~~need~~financial ~~them.~~results Ifor wedetect ~~cannot~~fraud. ~~raise~~Consequently, ~~additional~~shareholders ~~funds~~could ~~when~~lose weconfidence ~~need~~in ~~them,~~ our ~~operations~~financial reporting and ~~prospects~~this ~~could~~may bedecrease ~~negatively~~the ~~affected~~trading price of our Common Stock.

•● IfOur weaudited ~~fail~~financial tostatements ~~manage~~included ~~our~~a ~~future~~statement ~~growth~~that ~~effectively,~~there weis ~~may~~a ~~not~~substantial bedoubt ~~able~~about our ability to ~~market~~continue as a going concern and ~~sell~~a continuation of negative financial trends could result in our ~~fuel~~inability ~~cells~~to ~~successfully~~continue as a going concern.

•● We ~~will~~have ~~rely~~incurred onlosses ~~complex~~since ~~machinery~~inception ~~for our operations~~ and ~~production~~we ~~involves~~expect athat ~~significant~~we ~~degree~~will ofcontinue ~~risk~~to ~~and~~incur ~~uncertainty~~losses infor ~~terms~~the offoreseeable ~~operational performance and costs~~future.

•● ~~Our~~We ~~future~~may ~~growth~~need isto ~~dependent~~raise ~~upon~~additional ~~the~~funds ~~market’s~~and ~~willingness~~these funds may not be available to ~~adopt~~us ~~our~~when ~~hydrogen-powered~~we ~~fuel~~need ~~cell~~them. If we cannot raise additional funds when we need them, our operations and ~~membrane~~prospects ~~technology~~could be negatively affected.

•● We continue to generate a low level of revenue from our core ~~product MEA and developing commercial sales to major organizations~~products.

•● ~~Future~~If ~~product~~we ~~recalls~~fail ~~could~~to ~~materially~~manage ~~adversely~~our ~~affect~~future ~~our~~growth ~~business~~effectively, ~~prospects,~~we ~~operating~~may ~~results~~not be able to market and ~~financial~~sell ~~condition~~our fuel cells successfully.

•● IfOur wefuture ~~are~~growth ~~unable~~is todependent ~~attract~~upon ~~and~~the ~~retain~~market’s ~~key~~willingness ~~employees~~to ~~and~~adopt ~~hire~~our ~~qualified~~hydrogen-powered ~~management, technical and~~ fuel cell and ~~system~~membrane ~~engineering personnel, our ability to compete could be harmed~~technology.

•● WeIf ~~have~~we ~~been~~are unable to attract and retain key employees and hire qualified management, technical and ~~may~~fuel incell ~~the~~and ~~future~~system beengineering personnel, ~~adversely~~our ~~affected~~ability byto ~~the~~compete ~~global~~could ~~COVID-19~~be ~~pandemic~~harmed.

•● Increases in costs, disruption of supply or shortage of raw materials could harm our business.

•● We are or may be subject to risks associated with strategic alliances or acquisitions.

•● We ~~may~~are ~~experience~~subject ~~difficulties~~to ~~integrating~~substantial ~~the~~regulation ~~operations~~and ofunfavorable ~~acquired~~changes ~~companies~~to, ~~into~~or ~~our~~failure ~~business~~by ~~and~~us into ~~realizing~~comply ~~the~~with, ~~expected~~these ~~benefits~~regulations ofcould ~~these~~substantially ~~acquisitions~~harm our business and operating results.

•● WeThe ~~are~~unavailability, ~~subject~~reduction toor ~~substantial~~elimination ~~regulation~~of government and ~~unfavorable~~economic ~~changes~~incentives ~~to,~~could orhave ~~failure~~a bymaterial usadverse toeffect ~~comply~~on ~~with~~our business, ~~these~~prospects, ~~regulations~~financial ~~could~~condition ~~substantially harm our business~~ and operating results.

•● We ~~face~~may ~~risks~~not ~~associated~~be ~~with~~able ~~our~~to ~~international~~obtain ~~operations,~~or ~~including~~agree ~~unfavorable~~on ~~regulatory,~~acceptable ~~political~~terms and conditions for all or a significant portion of the government grants, ~~tax~~loans and ~~labor~~other ~~conditions,~~incentives for which ~~could~~we ~~harm~~may apply in the future. As a result, our business and prospects may be adversely affected.

•● ~~The~~Obtaining ~~unavailability,~~the ~~reduction~~MIL-STD orcertification ~~elimination~~for ofthe ~~government~~Honey Badger and ~~economic~~advancing ~~incentives~~it ~~could~~for ~~have~~U.S. aarmy ~~material~~integration ~~adverse~~is ~~effect~~subject onto ~~our~~risks ~~business, prospects, financial condition~~ and ~~operating results~~uncertainty.

•● WeFailure ~~may not be able to obtain or agree on acceptable terms and conditions for all or a significant portion~~ of ~~the~~our ~~government~~information ~~grants,~~technology ~~loans~~systems ~~and~~could ~~other~~significantly ~~incentives~~disrupt ~~for which we may apply in~~ the ~~future.~~operation Asof ~~a result,~~ our business ~~and prospects may be adversely affected~~.

• We may need to defend ourselves against patent or trademark infringement claims, which may be time-consuming and cause us to incur substantial costs.

• Our business may be adversely affected if we are unable to protect our intellectual property rights from unauthorized use by third parties.

• Our patent applications may not issue as patents, which may have a material adverse effect on our ability to prevent others from commercially exploiting products similar to ours.

• Our management team has limited experience managing a public company.

• The SEC released a public statement regarding accounting for warrants which resulted in our warrants being accounted for as liabilities rather than as equity and a restatement of our previously issued financial statements.

• The restatement of the Company's financial statements in May 2021 has subjected us to additional risks and uncertainties, including increased professional costs and the increased possibility of legal proceedings.

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•Risks Related ~~Certain~~to Ownership of ~~our~~Our ~~warrants~~Common ~~are~~Stock ~~accounted for as a warrant liability~~ and ~~are recorded at fair value upon issuance with changes in fair value each period to be reported in earnings, which may have an adverse effect on the market price of our common stock.~~Warrants

•● ~~Obtaining~~Delaware ~~the~~law ~~MIL-STD~~and ~~certification~~our ~~for~~second ~~the~~amended ~~Honey~~and ~~Badger~~restated certificate of incorporation and ~~advancing~~second itamended ~~for~~and ~~U.S.~~restated ~~army~~bylaws ~~integration~~contain iscertain ~~subject~~provisions, including anti-takeover provisions, that limit the ability of stockholders to ~~risks~~take certain actions and ~~uncertainty~~could delay or discourage takeover attempts that stockholders may consider favorable.

•● ~~Cybersecurity~~An ~~risks~~active ~~and~~market ~~attacks,~~for ~~security incidents, and data breaches could compromise~~ our ~~intellectual~~securities ~~property~~may ornot ~~other proprietary information~~develop, ~~could~~which ~~disrupt~~would ~~our~~adversely ~~electronic~~affect ~~infrastructure,~~the ~~operations~~liquidity and ~~manufacturing,~~price ~~and~~of ~~could impact~~ our ~~competitive position, reputation, results of operations, financial condition, and cash flows~~securities.

•● ~~Our~~NASDAQ ~~global~~may ~~operations~~delist ~~are~~our ~~subject~~securities tofrom ~~data~~trading ~~privacy~~on ~~laws~~its ~~and~~exchange, ~~regulations~~which ~~that~~could ~~impose~~limit ~~significant~~investors’ ~~compliance~~ability ~~costs~~to ~~and~~make ~~create~~transactions ~~reputational~~in our securities and ~~legal~~subject ~~risk~~us to additional trading restrictions.

•● AOur ~~write-off~~common ofstock ~~all~~price ormay ~~part~~change ofsignificantly ~~our~~and ~~goodwill~~you orcould ~~other~~lose ~~intangible~~all ~~assets~~or ~~could~~part ~~adversely~~of ~~affect~~your ~~our~~investment ~~operating~~as ~~results~~a ~~and net worth~~result.

•● ~~Delaware~~As ~~law~~a ~~and~~public ~~our~~company, ~~second~~we ~~amended~~are ~~and~~subject ~~restated~~to ~~certificate~~additional oflaws, ~~incorporation~~regulations and ~~bylaws~~stock ~~contain~~exchange ~~certain~~listing ~~provisions~~standards, ~~including~~which ~~anti-takeover~~impose ~~provisions,~~additional ~~that~~costs ~~limit~~on ~~the~~us ~~ability~~and ofmay ~~stockholders~~strain toour ~~take~~resources ~~certain actions~~ and ~~could~~divert ~~delay~~our ormanagement’s ~~discourage takeover attempts that stockholders may consider favorable~~attention.

•● The ~~second~~exercise ~~amended and restated certificate~~ of ~~incorporation~~Warrants ~~designate a state or federal court located within the State of Delaware as the exclusive forum~~ for ~~substantially all disputes between us and~~ our ~~stockholders,~~common ~~and~~stock ~~also~~would ~~provide~~increase ~~that~~ the ~~federal~~number ~~district~~of ~~courts~~shares ~~will~~eligible ~~be the exclusive forum~~ for ~~resolving~~future ~~any~~resale ~~complaint~~in ~~asserting a cause of action arising under~~ the ~~Securities~~public ~~Act,~~market ~~each~~and ofresult ~~which~~in ~~could~~dilution ~~limit the ability of our stockholders~~ to ~~choose the judicial forum for disputes with us or~~ our ~~directors, officers, or employees~~stockholders.

•Risks Related ~~We may be required~~ to ~~take~~Our ~~write-downs~~Intellectual or write-offs, restructuring and impairment or other charges that could have a significant negative effect on our financial condition, results of operations and stock price, which could cause you to lose some or all of your investment.Property

•● AnOur ~~active~~ability ~~market~~to ~~for~~protect our ~~securities~~intellectual ~~may~~property ~~not develop, which would adversely affect the liquidity~~ and ~~price~~proprietary oftechnology ~~our~~is ~~securities~~uncertain.

•● ~~Nasdaq~~We may ~~delist~~need ~~our~~to ~~securities~~defend ~~from~~ourselves ~~trading~~against onpatent ~~its~~or ~~exchange~~trademark infringement claims, which ~~could~~may ~~limit~~be ~~investors’~~time-consuming ~~ability to make transactions in our securities~~ and ~~subject~~cause us to ~~additional~~incur ~~trading~~substantial ~~restrictions~~costs.

•● Our ~~common~~patent ~~stock~~applications ~~price~~may not issue as patents, which may ~~change~~have ~~significantly~~a ~~and~~material ~~you~~adverse ~~could~~effect ~~lose~~on ~~all~~our orability ~~part~~to ofprevent ~~your~~others ~~investment~~from ascommercially aexploiting ~~result~~products similar to ours.

•● ~~Because~~We ~~there~~may ~~are~~not nobe ~~current~~able ~~plans~~ to ~~pay~~protect ~~cash dividends on~~ our ~~common~~intellectual ~~stock~~property ~~for~~rights throughout the ~~foreseeable future, you may not receive any return on investment unless you sell your common stock at a price greater than what you paid for it~~world.

•Risks Related ~~Our~~to ~~stockholders~~the ~~may~~Offering ~~experience~~and ~~dilution~~the inOwnership ~~the~~of ~~future.~~our Common Stock

•● IfWe ~~securities~~have orbroad ~~industry~~discretion ~~analysts~~in dothe ~~not~~use ~~publish~~of ~~research~~the ornet ~~reports~~proceeds ~~about~~we ~~our~~receive ~~business,~~from ifthis ~~they~~offering ~~change~~and ~~their~~may ~~recommendations regarding our common stock or if our operating results do~~ not ~~meet~~use ~~their~~them ~~expectations, our common stock price and trading volume could decline~~effectively.

•● Future sales, orof ~~the~~substantial ~~perception~~amounts of ~~future sales, by us or~~ our ~~stockholders~~Common inStock ~~the public market~~ could ~~cause~~adversely affect the market price ~~for~~of our ~~common~~Common ~~stock to decline~~Stock.

•● AsThe atrading ~~public~~price ~~company,~~of weour ~~are~~Common ~~subject~~Stock has been and is likely to ~~additional~~continue ~~laws,~~to ~~regulations~~be ~~and~~highly ~~stock~~volatile ~~exchange~~and ~~listing~~could ~~standards,~~be ~~which~~subject ~~impose~~to ~~additional~~wide ~~costs~~fluctuations onin usresponse ~~and~~to ~~may~~various ~~strain~~factors, ~~our~~some ~~resources~~of ~~and~~which ~~divert~~are beyond our ~~management’s attention~~control.

•● WeIf ~~are~~securities anor ~~emerging~~industry ~~growth~~analysts ~~company~~do ~~within~~not ~~the~~publish ~~meaning~~research ofor ~~the~~publish ~~Securities~~inaccurate ~~Act,~~or ~~and~~unfavorable ifresearch weabout ~~take~~our ~~advantage of certain exemptions from disclosure requirements available to emerging growth companies~~business, ~~this could make~~ our ~~securities~~stock ~~less~~price ~~attractive to investors~~ and ~~may~~trading ~~make~~volume itcould ~~more difficult to compare our performance with other public companies~~decline.

●

We have not paid dividends in the past and do not expect to pay dividends in the future, and any return on investment may be limited to the value of our stock.

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• We may redeem unexpired public warrants prior to their exercise at a time that is disadvantageous for warrant holders.

• Changes in accounting standards and subjective assumptions, estimates and judgments by management related to complex accounting matters could significantly affect our financial condition and results of operations.

• The exercise of Warrants for our common stock would increase the number of shares eligible for future resale in the public market and result in dilution to our stockholders.

Corporate Information

Our principal executive offices are located at ~~200~~5637 ~~Clarendon Street~~La Ribera St., ~~Boston~~Suite A, MALivermore, ~~02116.~~CA ~~Our~~94550 and our telephone number is (~~857~~925) ~~264~~455-~~7035,~~9400. We ~~and~~maintain ~~our~~a website ~~address~~at is https://www.advent.energy. Information ~~contained~~available on our ~~website~~websites ~~or connected thereto~~ is ~~provided~~not ~~for~~incorporated ~~textual~~by reference ~~only~~in and ~~does not constitute part of, and~~ is not ~~incorporated~~deemed bya ~~reference~~part ~~into,~~of this prospectus ~~or the registration statement of which it forms a part~~.

Implications of Being a Smaller Reporting Company

We are a smaller reporting company as defined in the Exchange Act. We may take advantage of certain of the scaled disclosures available to smaller reporting companies and will be able to take advantage of these scaled disclosures for so long as (i) the market value of our voting and non-voting common stock held by non-affiliates is less than $250 million measured on the last business day of our second fiscal quarter or (ii) our annual revenue is less than $100 million during the most recently completed fiscal year and the market value of our voting and non-voting common stock held by non-affiliates is less than $700 million measured on the last business day of our second fiscal quarter. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our annual reports on Form 10-K and have reduced disclosure obligations regarding executive compensation, and if we are a smaller reporting company with less than $100 million in annual revenue, we would not be required to obtain an attestation report on internal control over financial reporting issued by our independent registered public accounting firm.

Reverse Split

On May 13, 2024, we effected a 1-for-30 reverse split of our outstanding Common Stock. All share and per share data set forth in this prospectus have been retroactively adjusted to reflect these reverse share split(s).

Going Concern

As of December 31, 2024, management and the Company’s auditors, M&K CPAS, PLLC have determined there is substantial doubt about the Company’s ability to continue as a going concern. The Company may need to obtain funds to support its working capital, the methods of which include, without limitation, the following:

●

Equity financing;

●

Other available sources of financing (including debt) from banks and other financial institutions; and

●

Financial support and credit guarantee commitments from the Company’s related parties.

There can be no assurance that the Company will be successful in securing sufficient funds to sustain its operations.

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~~THE OFFERING~~The Offering

We are registering the resale by the Selling Securityholders or their permitted transferees of (i) 5,124,846 shares of our common stock that were issued to F.E.R. fischer Edelstahlrohre GmbH; and (ii) an aggregate of 5,028,019 shares of our common stock held by other Selling Securityholders. Any investment in the securities offered hereby is speculative and involves a high degree of risk. You should carefully consider the information set forth under “Risk Factors” on page 13 of this prospectus.

Shares of our common stock offered by the Selling Stockholder:		987,036 shares of common stock

Shares of our common stock outstanding prior to the offering:		2,670,286 shares⁽¹⁾

Shares of common stock outstanding after giving effect to the issuance of the shares registered hereunder:		3,657,322 shares. The actual number of shares outstanding after the offering will vary depending upon the actual number of shares we issue and sell to Hudson Global under the Purchase Agreement after the date of this prospectus.

Use of proceeds:		We will not receive any proceeds from the resale of shares of common stock included in this prospectus by the Selling Stockholder. However, we may receive up to $52 million in aggregate gross proceeds under the Purchase Agreement from sales of common stock that we may elect to make to the Selling Stockholder pursuant to the Purchase Agreement, if any, from time to time in our sole discretion, from and after the date of this prospectus. We expect to use the net proceeds that we receive from sales of our common stock to the Selling Stockholder, if any, under the Purchase Agreement to fund the operating expenses and capital expenses for product development and plan to make substantial investments over the next several years, among others, in new production equipment and warehousing, systems assembly line, MEA assembly automation, aeronautical stacks, facility expansion, new hirings and general corporate purposes, including, but not limited to, for use with respect to certain projects of our subsidiary, Advanced Energy Technologies S.A. We do not currently have specific plans or commitments with respect to the net proceeds from this offering and, accordingly, we are unable to quantify the allocations of such proceeds among various potential uses. See “Use of Proceeds” on page 41 of this prospectus.

Risk Factors:		Investing in our common stock involves a high degree of risk. See “Risk Factors” beginning on page 12 of this prospectus and in the documents incorporated by reference into this prospectus for a discussion of certain factors to consider carefully before deciding to purchase any shares of our common stock.

Ticker symbols:		“ADN” and “ADNWW” for the common stock and warrants, respectively.

~~Issuance~~(1) The number of ~~Common~~shares ~~Stock~~of common stock outstanding is based on 2,670,286 shares of common stock outstanding as of August 14, 2025 and does not include (a) 1,318,477 shares issuable upon exercise of outstanding warrants, and (b) 33,886 shares of common stock issuable upon exercise of outstanding options, 4,411 shares issuable upon vesting of outstanding restricted stock units and 530,976 shares of common stock reserved for future issuance of awards pursuant to the Company’s 2021 Equity Incentive Plan. Unless otherwise indicated, this prospectus assumes no exercise of outstanding stock options or warrants and no settlement of outstanding restricted stock units.

The following information is as of March 31, 2022 and does not give effect to issuances of our common stock after such date.

Shares of our Common stock offered by the Selling Securityholders in this offering

10,152,865 shares

Shares of our common stock outstanding prior to this offering

51,253,591 shares(1)

Shares of our common stock outstanding immediately after this offering

51,253,591 shares

Use of proceeds

The Selling Securityholders will receive all of the net proceeds from this offering and we will not receive any proceeds from the sale of shares of common stock in this offering.

Ticker symbols

“ADN” and “ADNWW” for the common stock and warrants, respectively.

(1) The number of shares of common stock outstanding is based on 51,253,591 shares of common stock outstanding as of March 31, 2022 and does not include:

• 6,915,892 shares of common stock reserved for issuance for awards in accordance with the 2021 Equity Incentive Plan; and

• 22,029,279 shares of common stock underlying the public warrants, 3,940,278 shares of common stock underlying the placement warrants and 400,000 shares of common stock underlying the working capital warrants.

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MARKET PRICE, TICKER SYMBOL AND DIVIDEND INFORMATION

Market Price and Ticker Symbol

Our common stock and warrants are currently listed on Nasdaq under the symbols “ADN” and “ADNWW”, respectively.

The closing price of the common stock and warrants on April 20, 2022, was $2.21 and $0.4289, respectively.

Holders

As of March 31, 2022, there were approximately 50 holders of record of shares of our common stock and 6 holders of record of our warrants. Such numbers do not include DTC participants or beneficial owners holding shares through nominee names.

Dividend Policy

We have never declared or paid any dividends on our common stock. We do not anticipate declaring or paying any cash dividends on our capital stock in the foreseeable future. The payment of cash dividends in the future will be dependent upon our revenues and earnings, if any, capital requirements and general financial condition. The payment of any cash dividends will be within the discretion of the board of directors at such time.

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RISK FACTORS

An investment in our securities involves a high degree of risk. You should carefully consider the ~~risks~~following ~~described~~risk ~~below~~factors, astogether ~~well as~~ with the other information ~~included~~contained in this prospectus, ~~including~~before ~~“Cautionary~~purchasing ~~Note~~our ~~Regarding~~securities. ~~Forward-Looking~~We ~~Statements,”~~have ~~“Management’s~~listed ~~Discussion~~below ~~and~~(not ~~Analysis~~necessarily ofin order ~~Financial~~of ~~Condition~~importance ~~and~~or ~~Results~~probability of ~~Operations”~~occurrence) ~~and~~what ~~the~~we ~~consolidated~~believe ~~financial~~to ~~statements~~be ~~and~~ the ~~related~~most ~~notes~~significant ~~thereto~~risk ~~included~~factors ~~elsewhere~~applicable into ~~this prospectus~~us, ~~before~~but ~~making~~they ando ~~investment~~not constitute ~~decision.~~all ~~Our~~of ~~business,~~the ~~prospects,~~risks ~~financial~~that ~~condition,~~may ~~or operating~~be ~~results~~applicable. ~~could~~Any beof ~~harmed~~the byfollowing ~~any~~factors ofcould ~~these~~harm ~~risks~~our business, asfinancial ~~well~~condition, asresults of ~~other~~operations ~~risks~~or ~~not~~prospects, ~~currently~~and ~~known~~could toresult usin a partial or ~~that~~complete weloss ~~currently~~of ~~consider~~your ~~immaterial~~investment. ~~The~~Some ~~trading~~statements ~~price~~in ofthis ~~our~~prospectus, ~~securities~~including statements ~~could~~in ~~decline~~the ~~due~~following torisk ~~any of these risks~~factors, ~~and,~~constitute asforward-looking astatements. ~~result,~~Please ~~you may~~refer ~~lose~~to ~~all~~the orsection ~~part~~titled of“Cautionary Statement ~~your~~Regarding ~~investment.~~Forward-Looking Statements.”

~~Risk~~Risks Related ~~Factors Relating~~ to ~~Our~~the ~~Operations and Business~~Offering

The sale or issuance of our common stock to Hudson Global may cause dilution and the sale of the shares of common stock acquired by Hudson Global, or the perception that such sales may occur, could cause the price of our common stock to fall.

On August 14, 2025, we entered into the Purchase Agreement with Hudson Global, which provides that, upon the terms and subject to the conditions and limitations set forth therein, we have the right, but not the obligation, to sell to Hudson Global up to $52,000,000 of our common stock from time to time over the 24-month term of the Purchase Agreement. The shares of our common stock that may be issued under the Purchase Agreement may be sold by us to Hudson Global at our discretion from time to time over a 24-month period commencing after the satisfaction of certain conditions set forth in the Purchase Agreement, including that the SEC has declared effective the registration statement of which this prospectus is a part and that such registration statement remains effective. The purchase price for the shares that we may sell to Hudson Global under the Purchase Agreement will fluctuate based on the price of our common stock. Depending on market liquidity at the time, sales of such shares may cause the trading price of our common stock to fall.

Subject to the terms of the Purchase Agreement, we generally have the right to control the timing and amount of any future sales of our shares to Hudson Global. Additional sales of our common stock, if any, to Hudson Global will depend upon market conditions and other factors to be determined by us. We may ultimately decide to sell to Hudson Global all, some, or none of the additional shares of our common stock that may be available for us to sell pursuant to the Purchase Agreement. If and when we do sell shares to Hudson Global, after Hudson Global has acquired the shares, Hudson Global may resell all or some of those shares at any time or from time to time in its discretion. Therefore, sales to Hudson Global by us could result in substantial dilution to the interests of other holders of our common stock. Additionally, the sale of a substantial number of shares of our common stock to Hudson Global, or the anticipation of such sales, could make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise wish to effect sales.

Our management will have broad discretion over the use of the net proceeds from our sale of shares of common stock to Hudson Global, you may not agree with how we use the proceeds and the proceeds may not be invested successfully.

Our management will have broad discretion as to the use of the net proceeds from our sale of shares of common stock to Hudson Global, and we could use them for purposes other than those contemplated at the time of commencement of this offering. Accordingly, you will be relying on the judgment of our management with regard to the use of those net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. It is possible that, pending their use, we may invest those net proceeds in a way that does not yield a favorable, or any, return for us. The failure of our management to use such funds effectively could have a material adverse effect on our business, financial condition, operating results and cash flows.

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It is not possible to predict the actual number of shares we will sell under the Purchase Agreement to the Selling Stockholder, or the actual gross proceeds resulting from those sales.

Because the purchase price per share to be paid by Hudson Global for the shares of common stock that we may elect to sell to Hudson Global under the Purchase Agreement, if any, will fluctuate based on the market prices of our common stock during the applicable period for each purchase made pursuant to the Purchase Agreement, if any, it is not possible for us to predict, as of the date of this prospectus and prior to any such sales, the number of shares of common stock that we will sell to Hudson Global under the Purchase Agreement, the purchase price per share that Hudson Global will pay for shares purchased from us under the Purchase Agreement, or the aggregate gross proceeds that we will receive from those purchases by Hudson Global under the Purchase Agreement, if any.

Moreover, although the Purchase Agreement provides that we may sell up to an aggregate of $52,000,000 worth of our common stock to Hudson Global (the “Total Commitment”), 987,036 shares of our common stock, are being registered for resale by Hudson Global under the registration statement that includes this prospectus, among which we may elect to sell to Hudson Global, in our sole discretion, from time to time from and after the Commencement Date under the Purchase Agreement up to $52,000,000 shares worth of common stock. If, after the Commencement Date, the price of our stock declines and we elect to sell to Hudson Global shares of common stock being registered for resale under this prospectus that are available for sale by us to Hudson Global under the Purchase Agreement, depending on the market prices of our common stock during the applicable period for each purchase made pursuant to the Purchase Agreement, the actual gross proceeds from the sale of all such shares may be substantially less than the $52,000,000 Total Commitment available to us under the Purchase Agreement, which could materially adversely affect our liquidity.

Based on our current stock price, if it becomes necessary for us to issue and sell to Hudson Global under the Purchase Agreement more than the 987,036 shares of our common stock in order to receive aggregate gross proceeds equal to the Total Commitment of $52,000,000 under the Purchase Agreement, we must file with the SEC one or more additional registration statements to register under the Securities Act the resale by Hudson Global of any such additional shares of our common stock we wish to sell from time to time under the Purchase Agreement, which the SEC must declare effective. Plus, we will need to obtain stockholder approval to issue shares of common stock in excess of 534,031 shares (the “Exchange Cap”), which is 19.99% of the shares of common stock outstanding immediately prior to the execution of the Purchase Agreement, under the Purchase Agreement in accordance with applicable Nasdaq rules, in each case, before we may elect to sell any additional shares of our common stock to Hudson Global under the Purchase Agreement. Any issuance and sale by us under the Purchase Agreement of a substantial amount of shares of common stock in addition to the 987,036 shares of common stock being registered for resale by Hudson Global under this prospectus could cause additional substantial dilution to our stockholders. The number of shares of our common stock ultimately offered for sale by Hudson Global is dependent upon the number of shares of common stock, if any, we ultimately sell to Hudson Global under the Purchase Agreement.

The number of shares that may be issued to Hudson Global under the terms of the Purchase Agreement may be limited due to the requirements of the Nasdaq Capital Market.

Under Nasdaq Listing Rule 5635(d), in the event we endeavor to issue more than 534,031 shares, we need stockholder approval for the potential issuance and sale of 20% or more of our common stock in order to issue shares of common stock to receive all the $52,000,000 Total Commitment proceeds under the Purchase Agreement. We do not currently plan to seek such stockholder approval. In the event we are required to seek stockholder approval, there is no assurance that such stockholder approval will be obtained which could adversely prevent us from receiving all the $52,000,000 Total Commitment under the Purchase Agreement.

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Investors who buy shares at different times will likely pay different prices.

Pursuant to the Purchase Agreement, we will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares sold to Hudson Global. If and when we do elect to sell shares of our common stock to Hudson Global pursuant to the Purchase Agreement, after Hudson Global has acquired such shares, Hudson Global may resell all, some or none of such shares at any time or from time to time in its discretion and at different prices. As a result, investors who purchase shares from Hudson Global in this offering at different times will likely pay different prices for those shares, and so may experience different levels of dilution and in some cases substantial dilution and different outcomes in their investment results.

Investors may experience a decline in the value of the shares they purchase from Hudson Global in this offering as a result of future sales made by us to Hudson Global at prices lower than the prices such investors paid for their shares in this offering.

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Risks Related to Our Operations and Business

We have identified material weaknesses in our system of internal controls pursuant to Section 404 of the Sarbanes-Oxley Act of 2002. If not remediated, these material weaknesses could result in material misstatements in our consolidated financial statements. We may be unable to develop, implement and maintain appropriate controls in future periods.

Our management identified material weaknesses in our internal control processes. A material weakness is a deficiency, or a combination of deficiencies, in internal control, such that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected and corrected on a timely basis. Management has concluded that, because of these material weaknesses, we were unable to timely file our annual report on Form 10-K for the fiscal year ended December 31, 2023, and our quarterly reports on Form 10-Q for the quarters ended March 31, 2024, June 30, 2024, and September 30, 2024. These deficiencies primarily relate to our lack of an effective internal control structure and sufficient financial reporting and accounting personnel due to the resignation of key control operators in early 2024 including the Company’s Chief Financial Officer and then the subsequent resignation of his successor soon thereafter. As a result of the material weaknesses, the Company’s management, under the supervision of the Audit Committee of the Board of Directors and with participation of the Company’s Chief Executive Officer and Interim Chief Financial Officer, concluded that the Company’s internal control over financial reporting was not effective as of December 31, 2023 and December 31, 2024 (including the interim periods therein).

Although we are working to remedy the ineffectiveness of the Company’s internal control over financial reporting, there can be no assurance as to when the remediation plan will be fully developed and implemented. Until our remediation plan is fully implemented, our management will continue to devote significant time, attention and financial resources to these efforts. If we do not complete our remediation in a timely fashion, or at all, or if our remediation plan is inadequate, there will continue to be an increased risk that we will be unable to timely file quarterly reports on Form 10-Q and Annual Reports on Form 10-K. Further and continued determinations that there are one or more material weaknesses in the effectiveness of the Company’s internal control over financial reporting could also reduce our ability to obtain financing or could increase the cost of any financing we obtain and require additional expenditures of both money and our management’s time to comply with applicable requirements. For more information relating to the Company’s internal control over financial reporting, the material weaknesses that existed as of December 31, 2024 and 2023, and the remediation activities undertaken by us, see Part IJ, Item 9A, “Controls and Procedures” of our Annual Report on Form 10-K for the year ended December 31, 2024 (the “2024 10-K”).

If we fail to maintain an effective system of internal controls, we may not be able to accurately report our financial results or detect fraud. Consequently, shareholders could lose confidence in our financial reporting, and this may decrease the trading price of our common stock.

We are subject to the reporting requirements of the Exchange Act, the Sarbanes-Oxley Act of 2002, or SOX, and Nasdaq rules and regulations. SOX requires, among other things, that we maintain effective disclosure controls and procedures and internal control over financial reporting. We perform system and process evaluation and testing of our internal controls over financial reporting to allow management to report on the effectiveness of our internal controls over financial reporting in our Annual Report on Form 10-K filing for that year, as required by Section 404 of SOX. As mentioned herein, we have identified material weaknesses in our internal control processes related to the separation of several members of our finance team. While we are currently working to remediate these material weaknesses, we cannot assure that, in the future, a material weakness or significant deficiency will not exist or otherwise be discovered. If that were to happen, it could harm our operating results and cause shareholders to lose confidence in our reported financial information. Any such loss of confidence would have a negative effect on the trading price of our securities.

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A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be satisfied. Internal control over financial reporting and disclosure controls and procedures are designed to give a reasonable assurance that they are effective to achieve their objectives. We cannot provide absolute assurance that all our possible future control issues will be detected. These inherent limitations include the possibility that judgments in our decision making can be faulty, and that isolated breakdowns can occur because of simple human error or mistake. The design of our system of controls is based in part upon assumptions about the likelihood of future events, and there can be no assurance that any design will succeed absolutely in achieving our stated goals under all potential future or unforeseeable conditions. Because of the inherent limitations in a cost-effective control system, misstatements due to error could occur and not be detected. This and any future failures could cause investors to lose confidence in our reported financial information, which could have a negative impact on our financial condition and stock price.

Our audited financial statements included a statement that there is a substantial doubt about our ability to continue as a going concern and a continuation of negative financial trends could result in our inability to continue as a going concern.

Our audited financial statements as of and for the year ended December 31, 2024, were prepared on the assumption that we would continue as a going concern. Our audited financial statements as of and for the year ended December 31, 2024, did not include any adjustments that might result from the outcome of this uncertainty. Our management has determined that there is a substantial doubt about our ability to continue as a going concern over the next twelve months based on the insufficient amount of cash and cash equivalents and net revenue from operations, as of the financial statement filing date and our independent registered public accounting firm has included an explanatory paragraph in their report on our financial statements as of and for the year ended December 31, 2024, stating that we have concluded that a substantial doubt exists about our ability to continue as a going concern. In addition to cash inflows from operations, the Company pursues additional debt and/or equity funding.

We have incurred losses since inception and we expect that we will continue to incur losses for the foreseeable future.

We have not been profitable since operations commenced, and we may never achieve or sustain profitability. We expect to continue to incur net losses and generate negative cash flows until we can produce sufficient revenues and gross profit to cover our costs. We may never become profitable. Even if we do achieve profitability, we may be unable to sustain or increase our profitability in the future. We will require significant additional capital to continue operations and to implement our business strategy. We cannot estimate with reasonable certainty the actual amounts necessary to successfully complete the development, manufacture and commercialization of our products and there is no certainty that we will be able to raise the necessary capital on reasonable terms or at all.

We may be unable to adequately control the costs associated with our operations.

We will require significant capital to develop and grow our business, including developing and manufacturing our fuel cells and building Advent’s brand. We expect to incur significant expenses which will impact our profitability, including research and development expenses, raw material procurement costs, sales and distribution expenses as we build Advent’s brand and market our fuel cells, and general and administrative expenses as we scale our operations. Our ability to become profitable in the future will not only depend on our ability to successfully market our fuel cells and other products and services, but also to control our costs. If we are unable to cost efficiently design, manufacture, market, sell, distribute and service our fuel cells, our margins, profitability and prospects would be materially and adversely affected.

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We may need to raise additional funds and these funds may not be available to us when we need them. If we cannot raise additional funds when we need them, our operations and prospects could be negatively affected.

The scale-up of production of our fuel cells, membranes and electrodes, together with the associated investment in our assembly line and product development activities, will consume capital. ~~While~~To weensure ~~expect~~ that we will have sufficient capital to fund our planned operations ~~through to breakeven~~, we ~~may need~~intend to raise additional funds through the issuance of equity, equity related or debt securities, or through obtaining credit from government or financial institutions. This capital will be necessary to fund our ongoing operations, continue research, development and design efforts, improve infrastructure, and introduce new technologies. We cannot be certain that additional funds will be available to us on favorable terms when required, or at all. If we cannot raise additional funds when we need them, our financial condition, results of operations, business and prospects could be materially adversely affected.

We continue to generate a low level of revenue from our core products.

Based on conversations with existing customers and incoming inquiries from new customers, we anticipate substantial increased demand for our MEAs and fuel cell systems from a wide range of customers as we scale up our production facilities and testing capabilities, and as the awareness our MEA capabilities become widely known in the industry. We expect both existing customers to increase order volume, and to generate substantial new orders from major organizations, with some of whom we are already in discussions regarding prospective commercial partnerships and joint development agreements. As of December 31, 2024, we were still generating a low level of revenues compared to our future projections and have not made major commercial sales to global OEM organizations.

If we fail to manage our future growth effectively, we may not be able to market and sell our fuel cells successfully.

Any failure to manage our growth effectively could materially and adversely affect our business, prospects, operating results and financial condition. We intend to expand our operations significantly. Our future expansion will include:

•● training new personnel;

•● forecasting production and revenue;

•● geographic expansion;

•● controlling expenses and investments in anticipation of expanded operations;

•● entry into new material contracts;

•● establishing or expanding design, production, licensing and sales; and

•● implementing and enhancing administrative infrastructure, systems and processes.

We intend to hire additional personnel, including design and production personnel. Because our technologies are different from traditional electric vehicle battery technology, individuals with sufficient training in alternative fuel and electric vehicles may not be available to hire, and as a result, we will need to expend significant time and expense training the employees we do hire. Competition for individuals with experience designing and manufacturing hydrogen fuel cells is high, and we may not be able to attract, integrate, train, motivate or retain additional highly qualified personnel in the future. The failure to attract, integrate, train, motivate and retain these additional employees could seriously harm our business and prospects.

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We will rely on complex machinery for our operations and production involves a significant degree of risk and uncertainty in terms of operational performance and costs.

We will rely heavily on complex machinery for our operations and our production will involve a significant degree of uncertainty and risk in terms of operational performance and costs. Our membrane and fuel cell production plant will consist of large-scale machinery combining many components. The production plant components are likely to suffer unexpected malfunctions from time to time and will depend on repairs and spare parts to resume operations, which may not be available when needed. Unexpected malfunctions of the production plant components may significantly affect the intended operational efficiency. Operational performance and costs can be difficult to predict and are often influenced by factors outside of our control, such as, but not limited to, scarcity of natural resources, environmental hazards and remediation, costs associated with decommissioning of machines, labor disputes and strikes, difficulty or delays in obtaining governmental permits, damages or defects in electronic systems, industrial accidents, fire, and seismic activity and natural disasters. Should operational risks materialize, it may result in the personal injury to or death of workers, the loss of production equipment, damage to manufacturing facilities, monetary losses, delays and unanticipated fluctuations in production, environmental damage, administrative fines, increased insurance costs and potential legal liabilities, all which could have a material adverse effect on our business, results of operations, cash flows, financial condition or prospects.

Our future growth is dependent upon the market’s willingness to adopt our hydrogen-powered fuel cell and membrane technology.

Our growth is highly dependent upon the adoption by the automotive, aerospace, power and energy industries. If the market for our fuel cells and membranes does not develop at the rate or to the extent that we expect, our business, prospects, financial condition and operating results will be harmed. The market for alternative fuel and energy storage systems is still new and is characterized by rapidly changing technologies, price competition, numerous competitors, evolving government regulation and industry standards and uncertain customer demands and behaviors.

Factors that may influence the adoption of our fuel cell and membrane technology include:

•● perceptions about safety, design, performance and cost, especially if adverse events or accidents occur that are linked to the quality or safety of alternative fuel or electric vehicles;

•● improvements in the fuel economy of internal combustion engines and battery powered vehicles;

•● the availability of service for alternative fuel vehicles;

•● volatility in the cost of energy, oil, gasoline and hydrogen;

•● government regulations and economic incentives promoting fuel efficiency, alternate forms of energy, and regulations banning internal combustion engines;

•● the availability of tax and other governmental incentives to sell hydrogen;

•● volatility in the cost of energy, oil, gasoline and hydrogen;

•● government regulations and economic incentives promoting fuel efficiency, alternate forms of energy, and regulations banning internal combustion engines;

•● the availability of tax and other governmental incentives to sell hydrogen;

•● perceptions about and the actual cost of alternative fuel; and

•● macroeconomic factors.

~~We Continue to Generate a Low Level of Revenue from our core product MEA and Developing Commercial Sales to Major Organizations.~~ 18

~~Based~~Table ~~on conversations with existing customers and incoming inquiries from new customers, we anticipate substantial increased demand for our MEAs from a wide range~~ of customers as we scale up our production facilities and testing capabilities, and as the awareness our MEA capabilities become widely known in the industry. We expect both its existing customers to increase order volume, and to generate substantial new orders from major organizations, with some of whom it is already in discussions regarding prospective commercial partnerships and joint development agreements. As of December 31, 2021, we were still generating a low level of revenues compared to our future projections and have not made any commercial sales to major organizations.Contents

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Future product recalls could materially adversely affect our business, prospects, operating results and financial condition.

Any product recall in the future may result in adverse publicity, damage our brand and materially adversely affect our business, prospects, operating results and financial condition. In the future, we may voluntarily or involuntarily, initiate a recall if any of our fuel cells or membranes prove to be defective. Such recalls involve significant expense and diversion of management attention and other resources, which could adversely affect our brand image in our target markets, as well as our business, prospects, financial condition and results of operations.

If we are unable to attract and retain key employees and hire qualified management, technical and fuel cell and system engineering personnel, our ability to compete could be harmed.

Our success depends, in part, on our ability to retain our key personnel. The unexpected loss of or failure to retain one or more of our key employees could adversely affect our business, including our recent turnover in the finance function. Our success also depends, in part, on our continuing ability to identify, hire, attract, train and develop other highly qualified personnel.

Competition for these employees can be intense, and our ability to hire, attract and retain them depends on our ability to provide competitive compensation. We may not be able to attract, assimilate, develop or retain qualified personnel in the future, and our failure to do so could adversely affect our business, including the execution of our global business strategy. Any failure by our management team to perform as expected may have a material adverse effect on our business, prospects, financial condition and results of operations.

We have been, and may in the future be, adversely affected by the global COVID-19 pandemic.

We face various risks related to epidemics, pandemics, and other outbreaks, including the recent COVID-19 pandemic. The impact of COVID-19, including changes in consumer and business behavior, pandemic fears and market downturns, and restrictions on business and individual activities, has created significant volatility in the global economy and led to reduced economic activity. The spread of COVID-19 has also impacted our potential customers and suppliers by disrupting the manufacturing, delivery and overall supply chain of fuel cell manufacturers and suppliers.

Actions taken around the world to help mitigate the spread of COVID-19 include restrictions on travel, quarantines in certain areas and forced closures for certain types of public places and businesses. COVID-19 and actions taken to mitigate its spread have had and are expected to continue to have an adverse impact on the economies and financial markets of many countries, including the geographical area in which Advent operates. For example, In May 2021, Advent’s research and development activities in Boston were limited by the restrictions imposed on laboratory work in the U.S., with laboratories being run at approximately 25% occupancy, with the result that certain business development activities have moved more slowly. Additionally, in Patras, Greece, approximately half of the Company’s workforce have worked from home during the temporary lockdowns imposed by the Greek authorities, although these have largely been in support functions. These measures limit operations in our U.S. and Greece locations and have and may continue to adversely impact our employees, research and development activities and operations and the operations of our suppliers, vendors and business partners, and may negatively impact our sales and marketing activities. We may take further actions as may be required by government authorities or that we determine are in the best interests of our employees, suppliers, vendors and business partners.

The extent to which the COVID-19 pandemic continues to impact our business, prospects and results of operations will depend on future developments, which are highly uncertain and cannot be predicted, including the duration and spread of the pandemic, its severity, the actions to contain the virus or treat its impact, and how quickly and to what extent normal economic and operating activities can resume. Even after the COVID-19 pandemic has subsided, we may continue to experience an adverse impact to our business as a result of the global economic impact, including any recession that has occurred or may occur in the future.

There are no comparable recent events that may provide guidance as to the effect of the spread of COVID-19 and a pandemic, and, as a result, the ultimate impact of the COVID-19 pandemic or a similar health epidemic is highly uncertain.

Increases in costs, disruption of supply or shortage of raw materials could harm our business.

Once we increase production, we may experience increases in the cost or a sustained interruption in the supply or shortage of raw materials. Any such increase or supply interruption could materially negatively impact our business, prospects, financial condition and operating results. We use various raw materials including precious group metals such as platinum; carbon black; polymer precursors, reactants, and solvents; as well as carbon cloth and carbon fiber paper. The prices for these raw materials fluctuate depending on market conditions and global demand and could adversely affect our business and operating results.

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metals such as platinum; carbon black; polymer precursors, reactants, and solvents; as well as carbon cloth and carbon fiber paper. The prices for these raw materials fluctuate depending on market conditions and global demand and could adversely affect our business and operating results.

We are or may be subject to risks associated with strategic alliances or acquisitions.

We have entered into, and may in the future enter into additional, strategic alliances, including joint ventures or minority equity investments with various third parties to further our business purpose. These alliances could subject us to a number of risks, including risks associated with sharing proprietary information, non-performance by the third party and increased expenses in establishing new strategic alliances, any of which may materially and adversely affect our business. We may have limited ability to monitor or control the actions of these third parties and, to the extent any of these strategic third parties suffers negative publicity or harm to their reputation from events relating to their business, we may also suffer negative publicity or harm to our reputation by virtue of our association with any such third party.

When appropriate opportunities arise, we may acquire additional assets, products, technologies or businesses that are complementary to our existing business. In addition to possible stockholder approval, we may need approvals and licenses from relevant government authorities for the acquisitions and to comply with any applicable laws and regulations, which could result in increased delay and costs, and may disrupt our business strategy if we fail to do so. Furthermore, acquisitions and the subsequent integration of new assets and businesses into our own require significant attention from our management and could result in a diversion of resources from our existing business, which in turn could have an adverse effect on our operations. Acquired assets or businesses may not generate the financial results we expect. Acquisitions could result in the use of substantial amounts of cash, potentially dilutive issuances of equity securities and exposure to potential unknown liabilities of the acquired business. Moreover, the costs of identifying and consummating acquisitions may be significant.

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We may experience difficulties integrating the operations of acquired companies into our business and in realizing the expected benefits of these acquisitions.

~~We completed the acquisition of SerEnergy and FES on August 31, 2021.~~ Acquisitions involve numerous risks, any of which could harm our business and negatively affect our financial condition and results of operations. The success of ~~our~~various ~~acquisition~~strategic ofacquisitions ~~FES~~that ~~and~~the ~~SerEnergy~~Company may make in the future will depend in part on our ability to realize the anticipated business opportunities from combining their and our operations in an efficient and effective manner. These integration processes could take longer than anticipated and could result in the loss of key employees, the disruption of each company’s ongoing businesses, tax costs or inefficiencies, or inconsistencies in standards, controls, information technology systems, procedures and policies, any of which could adversely affect our ability to maintain relationships with customers, employees or other third parties, or our ability to achieve the anticipated benefits of the acquisitions, and could harm our financial performance. If we are unable to successfully or timely integrate the operations of ~~FES~~such ~~and~~acquired ~~SerEnergy~~businesses with our business, we may incur unanticipated liabilities and be unable to realize the revenue growth, synergies and other anticipated benefits resulting from the acquisitions, or fully offset the costs of the acquisition, and our business, results of operations and financial condition could be materially and adversely affected.

We are subject to substantial regulation and unfavorable changes to, or failure by us to comply with, these regulations could substantially harm our business and operating results.

Our fuel cells and membranes are subject to substantial regulation under international, federal, state, and local laws. We expect to incur significant costs in complying with these regulations. Regulations related to alternative energy are currently evolving and we face risks associated with changes to these regulations, including but not limited to:

•● increased subsidies for corn and ethanol production, which could reduce the operating cost of vehicles that use ethanol or a combination of ethanol and gasoline; and

•● increased sensitivity by regulators to the needs of established automobile manufacturers with large employment bases, high fixed costs and business models based on the internal combustion engine, which could lead them to pass regulations that could reduce the compliance costs of such established manufacturers or mitigate the effects of government efforts to promote alternative fuel vehicles. Compliance with changing regulations could be burdensome, time consuming, and expensive. To the extent compliance with new regulations is cost prohibitive, our business, prospects, financial condition and operating results would be adversely affected.

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We face risks associated with our international operations, including unfavorable regulatory, political, tax and labor conditions, which could harm our business.

We face risks associated with our international operations, including possible unfavorable regulatory, political, tax and labor conditions, which could harm our business. We have international operations in ~~Greece~~Europe that are subject to the legal, political, regulatory and social requirements and economic conditions in these jurisdictions. We are subject to a number of risks associated with international business activities that may increase our costs, impact our ability to sell our fuel cells and membranes and require significant management attention. These risks include:

•● difficulty in staffing and managing foreign operations;

•● foreign government taxes, regulations and permit requirements, including foreign taxes that we may not be able to offset against taxes imposed upon us in the U.S., and foreign tax and other laws limiting our ability to repatriate funds to the U.S.;

•● fluctuations in foreign currency exchange rates and interest rates;

•● ~~U.S.~~increased ~~and~~inflation ~~foreign~~rates ~~government trade restrictions, tariffs~~ and ~~price~~cost orof ~~exchange controls~~goods;

~~• foreign labor laws, regulations and restrictions;~~20

•Table ~~changes~~of ~~in diplomatic and trade relationships;~~Contents

•● ~~political~~U.S. ~~instability,~~and ~~natural~~foreign ~~disasters~~government trade restrictions, ~~war~~tariffs orand ~~events~~price ofor ~~terrorism;~~exchange ~~and~~controls;

•● ~~the~~foreign ~~strength~~labor oflaws, ~~international~~regulations ~~economies.~~and restrictions;

●

changes in diplomatic and trade relationships;

●

political instability, natural disasters, war, or events of terrorism;

●

the escalation or continuation of armed conflict, hostilities or economic sanctions between countries or regions, including the current conflict between Russia and Ukraine;

●

the strength of international economies and economic relations between countries or regions; and

●

economic uncertainties and potential disruptions include a slow-down in the general economy.

If we fail to successfully address these risks, our business, prospects, operating results and financial condition could be materially harmed.

The unavailability, reduction or elimination of government and economic incentives could have a material adverse effect on our business, prospects, financial condition and operating results.

Any reduction, elimination or discriminatory application of government subsidies and economic incentives because of policy changes, the reduced need for such subsidies and incentives due to the perceived success of alternative energies or other reasons may result in the diminished competitiveness of the alternative fuel industry generally. This could materially and adversely affect the growth of the alternative fuel automotive markets and our business, prospects, financial condition and operating results.

While certain tax credits and other incentives for alternative energy production and alternative fuel vehicles have been available in the past, there is no guarantee these programs will be available in the future. If current tax incentives are not available in the future, our financial position could be harmed.

We may not be able to obtain or agree on acceptable terms and conditions for all or a significant portion of the government grants, loans and other incentives for which we may apply in the future. As a result, our business and prospects may be adversely affected.

We anticipate continuing to apply for federal and state grants, loans and tax incentives under government programs designed to stimulate the economy and support the production of alternative fuel vehicles and related technologies. We anticipate that in the future there will be new opportunities for us to apply for grants, loans and other incentives from the U.S., state and foreign governments. Our ability to obtain funds or incentives from government sources is subject to the availability of funds under applicable government programs and approval of our applications to participate in such programs. The application process for these funds and other incentives will likely be highly competitive. We cannot assure you that we will be successful in obtaining any of these additional grants, loans and other incentives. If we are not successful in obtaining any of these additional incentives and we are unable to find alternative sources of funding to meet our planned capital needs, our business and prospects could be materially adversely affected.

17Certain members of our management team have limited experience managing a public company.

~~TABLE~~Certain members OFof ~~CONTENTS~~our management team have limited experience managing a publicly traded company, interacting with public company investors and complying with the increasingly complex laws pertaining to public companies. Our management team may not successfully or efficiently manage the requirements of being a public company subject to significant regulatory oversight and reporting obligations under the federal securities laws and the scrutiny of securities analysts and investors. These new obligations and constituents will require significant attention from our management team and could divert their attention away from the day-to-day management of our business, which could materially and adversely affect our business, financial condition, operating results, cash flows and prospects.

~~We may need to defend ourselves against patent or trademark infringement claims, which may be time-consuming and cause us to incur substantial costs.~~21

~~Companies,~~Table organizations or individuals, including our competitors, may own or obtain patents, trademarks or other proprietary rights that would prevent or limit our ability to make, use, develop, license or sell our fuel cell and membrane technologies, which could make it more difficult for us to operate our business. We may receive inquiries from patent or trademark owners inquiring whether we infringe their proprietary rights. Companies owning patents or other intellectual property rights relating to fuel cells may allege infringement of ~~such rights. In response to a determination that we have infringed upon a third party’s intellectual property rights, we may be required to do one or more of the following:~~Contents

• cease development, sales, license or use of fuel cells or membranes that incorporate the asserted intellectual property;

• pay substantial damages;

• obtain a license from the owner of the asserted intellectual property right, which license may not be available on reasonable terms or at all; or

• redesign one or more aspects or systems of our fuel cells or membranes.

A successful claim of infringement against us could materially adversely affect our business, prospects, operating results and financial condition. Any litigation or claims, whether valid or invalid, could result in substantial costs and diversion of resources.

We also plan to license patents and other intellectual property from third parties and we may face claims that our use of this in-licensed technology infringes the intellectual property rights of others. In such cases, we will seek indemnification from our licensors. However, our rights to indemnification may be unavailable or insufficient to cover our costs and losses.

Our business may be adversely affected if we are unable to protect our intellectual property rights from unauthorized use by third parties.

Failure to adequately protect our intellectual property rights could result in our competitors offering similar products, potentially resulting in the loss of some of our competitive advantage and a decrease in our revenue, which would adversely affect our business, prospects, financial condition and operating results. Our success depends, at least in part, on our ability to protect our core technology and intellectual property. To accomplish this, we will rely on a combination of patents, trade secrets (including know-how), employee and third-party nondisclosure agreements, copyright, trademarks, intellectual property licenses and other contractual rights to establish and protect our rights in our technology.

The protection of our intellectual property rights will be important to our future business opportunities. However, the measures we take to protect our intellectual property from unauthorized use by others may not be effective for various reasons, including the following:

• any patent applications we submit may not result in the issuance of patents;

• the scope of our issued patents may not be broad enough to protect our proprietary rights;

• our issued patents may be challenged and/or invalidated by our competitors;

• the costs associated with enforcing patents, confidentiality and invention agreements or other intellectual property rights may make aggressive enforcement impracticable;

• current and future competitors may circumvent our patents; and

• our in-licensed patents may be invalidated, or the owners of these patents may breach our license arrangements.

Patent, trademark, and trade secret laws vary significantly throughout the world. Some foreign countries do not protect intellectual property rights to the same extent as do the laws of the U.S. Further, policing the unauthorized use of our intellectual property in foreign jurisdictions may be difficult. Therefore, our intellectual property rights may not be as strong or as easily enforced outside of the U.S.

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Our patent applications may not issue as patents, which may have a material adverse effect on our ability to prevent others from commercially exploiting products similar to ours.

We cannot be certain that we are the first inventor of the subject matter to which we have filed a particular patent application, or if we are the first party to file such a patent application. If another party has filed a patent application to the same subject matter as we have, we may not be entitled to the protection sought by the patent application. Further, the scope of protection of issued patent claims is often difficult to determine. As a result, we cannot be certain that the patent applications that we file will issue, or that our issued patents will afford protection against competitors with similar technology. In addition, our competitors may design around our issued patents, which may adversely affect our business, prospects, financial condition or operating results.

Our management team has limited experience managing a public company.

Most members of our management team have limited experience managing a publicly-traded company, interacting with public company investors and complying with the increasingly complex laws pertaining to public companies. Our management team may not successfully or efficiently manage our transition to being a public company subject to significant regulatory oversight and reporting obligations under the federal securities laws and the scrutiny of securities analysts and investors. These new obligations and constituents will require significant attention from our management team and could divert their attention away from the day-to-day management of our business, which could materially and adversely affect our business, financial condition, operating results, cash flows and prospects.

The SEC released a public statement regarding accounting for warrants which resulted in our warrants being accounted for as liabilities rather than as equity and a restatement of our previously issued financial statements.

On April 12, 2021, the staff of the SEC issued a public statement entitled “Staff Statement on Accounting and Reporting Considerations for Warrants issued by Special Purpose Acquisition Companies (“SPACs”) (the “Statement”). In the Statement, the SEC staff expressed its view that certain terms and conditions common to SPAC warrants may require the warrants to be classified as liabilities on the SPAC's balance sheet as opposed to equity. Since issuance, our warrants were accounted for as equity within our balance sheet, and after discussion and evaluation, including with our independent auditors, we have concluded that our warrants should be presented as liabilities with subsequent fair value remeasurement. Therefore, we conducted a valuation of our warrants and restated our previously issued financial statements, which resulted in unanticipated costs and diversion of management resources and may result in potential loss of investor confidence. Although we have now completed the restatement, we cannot guarantee that we will have no further inquiries from the SEC or Nasdaq regarding our restated financial statements or matters relating thereto. Any future inquiries from the SEC or Nasdaq as a result of the restatement of our historical financial statements will, regardless of the outcome, likely consume a significant amount of our resources in addition to those resources already consumed in connection with the restatement itself.

The restatement of the Company's financial statements in May 2021 has subjected us to additional risks and uncertainties, including increased professional costs and the increased possibility of legal proceedings.

As a result of the restatement of our financial statements discussed above, we have become subject to additional risks and uncertainties, including, among others, increased professional fees and expenses and time commitment that may be required to address matters related to the restatement, and scrutiny of the SEC and other regulatory bodies which could cause investors to lose confidence in the Company's reported financial information and could subject the Company to civil or criminal penalties or shareholder litigation. We could face monetary judgments, penalties or other sanctions that could have a material adverse effect on the Company's business, financial condition and results of operations and could cause its stock price to decline.

Certain of our warrants are accounted for as a warrant liability and are recorded at fair value upon issuance with changes in fair value each period to be reported in earnings, which may have an adverse effect on the market price of our common stock.

Following the restatement of our historical financial statements, we account for our warrants as a warrant liability and recorded at fair value upon issuance any changes in fair value each period reported in earnings as determined by the Company based upon a valuation report obtained from its independent third party valuation firm. The impact of changes in fair value on earnings may have an adverse effect on the market price of our common stock.

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Obtaining the MIL-STD certification for the Honey Badger and advancing it for U.S. army integration is subject to risks and uncertainty.

Obtaining the MIL-STD certification for the Honey Badger and advancing it for U.S. army integration is subject to risks and uncertainty, and may not be completed on the timeline ~~the~~we ~~Company expects~~expect, or at all.

Cybersecurity risks and attacks, security incidents, and data breaches could compromise our intellectual property or other proprietary information, could disrupt our electronic infrastructure, operations and manufacturing, and could impact our competitive position, reputation, results of operations, financial condition, and cash flows.

We rely upon ~~the~~our information technology and ~~data~~electronic ~~security~~ infrastructure and its capacity, reliability, and security in connection with various and critical aspects of our business activities. We also rely on our ability to expand and continually update these technologies and related infrastructure in response to the changing needs of our business and the risks presented. We face challenges related to supporting our older technologies and implementing necessary upgrades and the hardening of current technologies. In addition, some of these technologies are managed by third-party service providers and are not under our direct control. If we experience a problem with a critical technology, including during upgrades or new technology implementations, any resulting disruptions could have an adverse effect on our business ~~operations~~ operations and our performance.

Our business operations rely upon our electronic infrastructure and that of our third-party vendors, including to handle information and data such as intellectual property, personal information, protected information, financial information and other confidential and proprietary information related to our business and our employees, prospects, customers, suppliers and other business partners. While we maintain certain administrative, technical, and physical safeguards and take preventive and proactive measures to combat known and unknown cybersecurity risks, weour ~~currently~~work ~~are~~and ~~building~~processes to build out and ~~maturing~~mature our electronic infrastructure, controls, policies and safeguards is ongoing. There is no assurance that our current controls and our ongoing efforts will be sufficient to eliminate security risks.

Cyberattacks are increasing in frequency and evolving in nature. We and our third-party providers are at risk of attack through use of increasingly sophisticated methods, including malware, phishing, ransomware, and the deployment of technologies to find and exploit vulnerabilities. Like many organizations, we have been targeted by phishing attacks, for example. Our electronic infrastructure, and information technology systems maintained by our third-party providers, have been in the past, and may be in the future, subjected to attempts to gain unauthorized access, disable, destroy, maliciously control or cause other business disruptions. In some cases, it is difficult to anticipate or to detect immediately such incidents and any damage caused. While these types of incidents have not had a material impact on our business to-date, future incidents involving access to or improper use of our systems, or those of our third-parties, could compromise confidential, proprietary or otherwise sensitive information.

In addition, cyberattacks could negatively impact our reputation and our competitive position and could result in litigation with third parties, regulatory action, significant remediation costs, and loss of business and customers relationships, any of which could adversely impact our business, our financial condition, and our operating results. Although we maintain some insurance coverage, we cannot be certain that coverage would apply to cyber risks, that it may be adequate for liabilities incurred, or that any insurer will not accept or deny coverage of future claims.

We may experience problems with the operation of our electronic infrastructure or the technology systems of third parties on which we rely, as well as the development and deployment of new electronic infrastructure, that could adversely affect, or even disrupt, all or a portion of our operations until resolved. In addition, as a result of the COVID-19 pandemic a large percentage of our salaried employees continue to work remotely full or part-time. This remote working environment may pose a heightened risk for security breaches or other disruptions of our information technology environment.

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Our global operations are subject to data privacy laws and regulations that impose significant compliance costs and create reputational and legal risk.

Due to the international scope of our operations, we may be subject to a complex system of regulatory requirements regarding data privacy, such as the European Union General Data Protection Regulation and California’s Consumer Privacy Act and its amendments.

Our numerous foreign operations are governed by laws, rules and business practices that differ from those of the U.S. We cannot predict now our future data privacy risks or the nature, scope or effect of future regulatory requirements to which our operations might be subject or the manner in which existing laws might be administered or interpreted.

20Adverse developments affecting the financial services industry, such as actual events or concerns involving liquidity, defaults, or non-performance by financial institutions or transactional counterparties, could adversely affect the Company’s current and projected business operations and its financial condition and results of operations.

~~TABLE~~Actual events OFinvolving ~~CONTENTS~~limited liquidity, defaults, non-performance or other adverse developments that affect financial institutions, transactional counterparties or other companies in the financial services industry or the financial services industry generally, or concerns or rumors about any events of these kinds or other similar risks, have in the past and may in the future lead to market-wide liquidity problems. For example, on March 10, 2023, Silicon Valley Bank (SVB) was closed by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation (FDIC) as receiver. Similarly, on March 12, 2023, Signature Bank and Silvergate Capital Corp. were each swept into receivership. Although a statement by the Department of the Treasury, the Federal Reserve and the FDIC indicated that all depositors of SVB would have access to all of their money after only one business day of closure, including funds held in uninsured deposit accounts, borrowers under credit agreements, letters of credit and certain other financial instruments with SVB, Signature Bank or any other financial institution that is placed into receivership by the FDIC may be unable to access undrawn amounts thereunder. Although we are not a borrower or party to any such instruments with SVB, Signature or any other financial institution currently in receivership, if any of our lenders or counterparties to any such instruments were to be placed into receivership, we may be unable to access such funds. In addition, if any of our customers, suppliers or other parties with whom we conduct business are unable to access funds pursuant to such instruments or lending arrangements with such a financial institution, such parties’ ability to pay their obligations to us or to enter into new commercial arrangements requiring additional payments to us could be adversely affected. In this regard, counterparties to SVB credit agreements and arrangements, and third parties such as beneficiaries of letters of credit (among others), may experience direct impacts from the closure of SVB and uncertainty remains over liquidity concerns in the broader financial services industry.

~~A write-off~~ Failure of ~~all or part of~~ our ~~goodwill or~~information ~~other~~technology ~~intangible~~systems ~~assets~~ could ~~adversely~~significantly ~~affect~~disrupt ~~our~~the ~~operating~~operation ~~results~~of ~~and~~our ~~net worth~~business.

~~Goodwill~~Our business increasingly depends on the use of information technologies, which means that certain key areas such as research and ~~other~~development, production ~~intangible~~and ~~assets~~sales are to a ~~component~~large ofextent dependent on our ~~assets. As~~information asystems ~~part~~or those of third-party providers. Our ability to execute our ~~acquisition~~business ofplan ~~SerEnergy~~and to comply with regulatory requirements with respect to data control and ~~FES~~data onintegrity, ~~August 31~~depends, ~~2021~~in part, weon ~~recognized~~the continued ~~$29.4 million~~and inuninterrupted ~~goodwill~~performance of our information technology systems, or IT systems and ~~$19.8 million~~the inIT ~~other~~systems ~~intangible~~supplied ~~assets~~by third-party service providers. AsThese systems are vulnerable to damage from a variety of ~~December 31~~sources, ~~2021~~including telecommunications or network failures, malicious ~~goodwill~~human ~~was~~acts ~~$30~~and natural disasters.~~0 million~~ ~~and~~Moreover, ~~other~~despite ~~intangible~~network ~~assets~~security ~~were $23.3 million~~and backup measures, some of our ~~total~~servers ~~assets~~are ofpotentially vulnerable ~~$163~~to physical or electronic break-ins, computer viruses and similar disruptive problems.~~0 million.~~ WeDespite ~~may~~the precautionary measures we and our third-party service providers have taken to ~~write~~prevent ~~off~~unanticipated ~~all~~problems orthat ~~part~~could ofaffect our ~~goodwill~~IT systems, sustained or repeated ~~other~~system ~~intangible~~failures ~~assets~~or ifproblems ~~their~~arising ~~value~~during ~~becomes~~the ~~impaired.~~upgrade ~~Although~~of ~~this~~any ~~write-off~~of ~~would~~our beIT asystems ~~non-cash~~that ~~charge,~~interrupt itour ~~could~~ability ~~reduce~~to ~~our~~generate ~~earnings~~and maintain data, and in particular to operate our ~~financial~~proprietary ~~condition~~technology platform, could adversely affect our ability to operate our business.

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Risks Related to Ownership of Our Common Stock and Warrants

~~Delaware~~NASDAQ may ~~law~~delist ~~and~~ our ~~second~~securities ~~amended~~from ~~and restated~~trading ~~certificate~~on ofits ~~incorporation and amended and restated bylaws contain certain provisions~~exchange, ~~including~~which ~~anti-takeover~~could ~~provisions, that~~ limit ~~the~~investors’ ability ~~of stockholders~~ to ~~take~~make ~~certain~~transactions ~~actions~~in our securities and ~~could~~subject ~~delay~~us orto ~~discourage~~additional ~~takeover~~trading ~~attempts that stockholders may consider favorable~~restrictions.

Our securities, ~~second~~including ~~amended~~common stocks and ~~restated~~warrants, ~~certificate~~are ofcurrently ~~incorporation~~listed ~~and~~on ~~our amended~~the ~~and~~Nasdaq ~~restated~~Capital ~~bylaws~~Market. However, ~~and~~we ~~the~~cannot ~~Delaware~~assure ~~General~~you ~~Corporations~~that our ~~Law~~securities ~~(“DGCL”),~~will ~~contain~~continue ~~provisions~~to ~~that~~be ~~could~~listed ~~have~~on the ~~effect~~Nasdaq ofCapital ~~rendering~~Market ~~more~~in ~~difficult,~~the ~~delaying,~~future. orIn ~~preventing~~order anto ~~acquisition~~continue ~~deemed~~listing ~~undesirable by~~ our ~~board~~securities ofon the ~~directors~~Nasdaq ~~and therefore~~Capital ~~depress~~Market, ~~the~~we ~~trading~~must ~~price~~maintain ofcertain ~~our~~financial, ~~common~~distribution and stock. ~~These~~price ~~provisions~~levels. ~~could~~Generally, ~~also~~we ~~make~~must itmaintain ~~difficult~~a ~~for~~minimum amount in stockholders’ toequity ~~take~~(generally ~~certain actions~~$2,500,000) ~~including~~and ~~electing~~a ~~directors~~minimum ornumber ~~taking~~of ~~other~~holders ~~corporate~~of ~~actions,~~our ~~including~~securities ~~effecting~~(generally ~~changes~~300 inpublic ~~our management~~holders). Additionally, ~~Among~~we are required to demonstrate compliance with other ~~things,~~Nasdaq’s ~~our~~continued ~~second~~listing ~~amended~~requirements ~~and~~in ~~restated~~order ~~certificate~~to ofcontinue to ~~incorporation~~maintain ~~and~~the ~~amended~~listing ~~and~~of ~~restated~~our ~~bylaws~~securities ~~include~~on ~~provisions~~the ~~regarding:~~Nasdaq Capital Market.

•In the apast, ~~classified~~we ~~board~~have ofreceived ~~directors~~deficiency letters from Nasdaq regarding our failure to satisfy continued listing requirements and are currently not in compliance with ~~three-year~~all ~~staggered~~such ~~terms~~requirements. On May 24, ~~which~~2023, ~~could~~the ~~delay~~Company received a letter from the ~~ability~~Listing Qualifications Staff (the “Staff”) of ~~stockholders~~Nasdaq toStock ~~change~~Market LLC (“Nasdaq”) indicating that the ~~membership~~bid price of the Common Stock had closed below $1.00 per share for 30 consecutive business days and, as a ~~majority~~result, ofthe ~~our~~Company ~~board~~was ofnot ~~directors;~~in compliance with Nasdaq Listing Rule 5550(a)(2), which sets forth the minimum bid price requirement for continued listing on the Nasdaq Capital Market (the “Minimum Bid Requirement”).

•On May 13, 2024, the ~~ability~~Company ofeffectuated ~~our~~the ~~board~~Reverse ofStock ~~directors~~Split, toand ~~issue~~our ~~shares~~Common ofStock ~~preferred~~began ~~stock,~~trading ~~including~~on ~~“blank~~a ~~check”~~split-adjusted ~~preferred~~basis ~~stock~~on ~~and~~the Nasdaq toCapital ~~determine~~Market at the ~~price~~opening ~~and~~of ~~other~~trading ~~terms~~on ofMay 14, ~~those shares~~2024, ~~including~~in ~~preferences~~an ~~and~~effort ~~voting~~to ~~rights,~~comply ~~without~~with ~~stockholder~~the ~~approval,~~Minimum ~~which~~Bid ~~could~~Requirement. beThe ~~used~~Company has tosince ~~significantly~~received ~~dilute~~confirmation ~~the~~from ~~ownership~~Nasdaq ofthat ait ~~hostile~~has ~~acquirer;~~met the Minimum Bid Requirement.

•On April 17, 2024, we received a letter from Nasdaq notifying the ~~limitation~~Company that it is not in compliance with the periodic reporting requirements for continued listing set forth Nasdaq Listing Rule 5250(c)(1) (the “Timely Report Requirement”) due to the fact that the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “2023 10-K”) was not filed by the required due date of March 31, 2024 (the ~~liability~~“2023 10-K Delinquency Letter”). Additionally, on May 24, 2024, we received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its Quarterly Report on Form 10-Q for the quarter ended March 31, 2024 (the “First Quarter 10-Q”) by the required due date of May 14, ~~and~~2024 (the ~~indemnification~~“Q1 10-Q Delinquency Letter”). Further, on November 22, 2024, we received a letter from Nasdaq notifying the Company that it is not in compliance with the Timely Reporting Requirement due to the fact that the Company did not file its Quarterly Report on Form 10-Q for the quarter ended September 30, 2024 (the “Third Quarter 10-Q”) by the required due date of November 20, ~~our~~2024 (the ~~directors~~“Q2 10-Q Delinquency Letter”). On April 16, 2025, the Company also received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth in Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its Annual Report on Form 10-K for the fiscal year ended December 31, 2024 (the “2024 10-K”) by the required due date of April 16, 2025. Lastly, on May 22, 2025, the Company received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth in Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its Quarterly Report on Form 10-Q for the quarter ended March 31, 2025 (the “Q1 2025 10-Q”) by the required due date of May 15, 2025. The Company submitted compliance plans to Nasdaq setting forth its plan to file 2023 10-K, the First Quarter 10-Q, the Third Quarter 10-Q, the 2024 10-K and ~~officers;~~the Q1 2025 10-Q. The Company filed its 2023 10-K on August 13, 2024, its First Quarter 10-Q on October 15, 2024, its Third Quarter 10-Q on December 27, 2024, its 2024 10-K on June 6, 2025 and its Q1 2025 10-Q on June 30, 2025.

• the exclusive right of our board of directors to elect a director to fill a vacancy created by the expansion of our board of directors or the resignation, death or removal of a director, which prevents stockholders from being able to fill vacancies on our board of directors;24

•Table ~~the requirement that directors may only be removed from our board~~ of ~~directors for cause;~~Contents

•Additionally, on October 18, 2024, we received a ~~prohibition~~letter onfrom ~~stockholder~~Nasdaq ~~action~~notifying bythe ~~written~~Company ~~consent,~~that ~~which~~since ~~forces~~the ~~stockholder~~Company’s ~~action~~Form to10-Q befor ~~taken~~the atperiod ended anJune 30, ~~annual~~2024, orreported ~~special~~stockholders’ ~~meeting~~equity of ~~stockholders~~($2,879,000), and ~~could~~as ~~delay~~of the ~~ability~~date of ~~stockholders~~such letter the Company did not meet the alternatives of market value of listed securities or net income from continuing operations, the Company is no longer in compliance with Nasdaq’s Listing Rule requiring the Company to ~~force~~maintain ~~consideration~~a minimum of $2,500,000 in stockholders’ equity for continued listing. The Company submitted a ~~stockholder~~compliance ~~proposal~~plan orand supplement to ~~take~~Nasdaq ~~action~~setting forth its plan to increase its stockholders’ equity, ~~including~~and on April 16, 2025, received a letter from Nasdaq confirming that the ~~removal~~Company ofhad ~~directors;~~regained compliance with the minimum stockholders’ equity rule for continued listing.

•We cannot ~~the~~assure ~~requirement~~you that awe ~~special~~will ~~meeting~~be ofable ~~stockholders~~to ~~may~~meet beNasdaq’s ~~called~~continued ~~only~~listing byrequirements ~~our~~at ~~board~~all oftimes. ~~directors,~~If ~~the~~Nasdaq ~~chairperson~~delists of our ~~board~~securities from oftrading ~~directors,~~on ~~our~~its ~~chief~~exchange ~~executive~~and ~~officer~~we orare ~~our~~not ~~president~~able ~~(in~~to ~~the~~list ~~absence~~our ofsecurities aon ~~chief~~another ~~executive~~national ~~officer)~~securities exchange, ~~which~~we ~~could~~expect ~~delay~~our ~~the~~securities could ~~ability~~be ofquoted ~~stockholders~~on toan ~~force~~over-the-counter ~~consideration~~market. ofIf athis ~~proposal~~were or to ~~take action~~occur, ~~including~~we ~~the~~could ~~removal~~face ofsignificant ~~directors;~~material adverse consequences, including:

•● ~~controlling~~a ~~the~~limited ~~procedures~~availability ~~for the conduct and scheduling~~ of ~~board~~market ofquotations ~~directors~~for ~~and~~its ~~stockholder meetings~~securities;

•● ~~the~~reduced ~~requirement~~liquidity for ~~the~~its affirmative vote of holders of at least 65% of the voting power of all of the then outstanding shares of the voting stock, voting together as a single class, to amend, alter, change or repeal any provision of the second amended and restated certificate of incorporation or amended and restated bylaws, which could preclude stockholders from bringing matters before annual or special meetings of stockholders and delay changes in our board of directors and also may inhibit the ability of an acquirer to effect such amendments to facilitate an unsolicited takeover attemptsecurities;

•● ~~the~~a ~~ability~~determination ofthat our ~~board~~common ofstock ~~directors~~is toa ~~amend~~“penny ~~the~~stock” ~~amended~~which ~~and~~will ~~restated~~require ~~bylaws,~~brokers ~~which~~trading ~~may~~in ~~allow~~the ~~our~~common ~~board~~stock ofto ~~directors~~adhere to ~~take~~more ~~additional~~stringent ~~actions~~rules toand ~~prevent~~possibly anresult ~~unsolicited~~in ~~takeover~~a ~~and~~reduced ~~inhibit~~level ~~the ability~~ of antrading ~~acquirer~~activity toin ~~amend~~ the ~~amended~~secondary ~~and~~trading ~~restated~~market ~~bylaws~~for toour ~~facilitate an unsolicited takeover attempt~~securities; ~~and~~

21 ● a limited amount of news and analyst coverage; and

~~TABLE~~● OFa ~~CONTENTS~~decreased ability to issue additional securities or obtain additional financing in the future.

~~• advance notice procedures with which stockholders must comply to nominate candidates to~~ If our ~~board~~common ofstock ~~directors~~were ordelisted toand ~~propose~~determined ~~matters~~ to be ~~acted upon at~~ a ~~stockholders’~~“penny ~~meeting~~stock,” ~~which~~a ~~could~~broker-dealer ~~preclude~~may ~~stockholders~~find ~~from~~it ~~bringing~~more ~~matters~~difficult ~~before~~to ~~annual or special meetings of stockholders and delay changes in~~ trade our ~~board~~common ofstock ~~directors~~ and ~~also~~an investor may ~~discourage~~find orit ~~deter~~more adifficult ~~potential acquirer from conducting a solicitation of proxies~~ to ~~elect~~acquire ~~the~~or ~~acquirer’s~~dispose ~~own slate~~ of ~~directors~~our orcommon ~~otherwise~~stock ~~attempting~~in tothe ~~obtain~~secondary ~~control of surviving entity~~market.

If our common stock were removed from listing with The Nasdaq Capital Market, it may be subject to the so-called “penny stock” rules. The SEC has adopted regulations that define a “penny stock” to be any equity security that has a market price per share of less than $5.00, subject to certain exceptions, such as any securities listed on a national securities exchange, which is the exception on which we currently rely. For any transaction involving a “penny stock,” unless exempt, the rules impose additional sales practice requirements on broker-dealers, subject to certain exceptions. If our common stock were delisted and determined to be a “penny stock,” a broker-dealer may find it more difficult to trade our common stock and an investor may find it more difficult to acquire or dispose of our common stock on the secondary market.

Delaware law and our second amended and restated certificate of incorporation and second amended and restated bylaws contain certain provisions, including anti-takeover provisions, that limit the ability of stockholders to take certain actions and could delay or discourage takeover attempts that stockholders may consider favorable.

Our second amended and restated certificate of incorporation and our amended and restated bylaws, and the Delaware General Corporation Law (“DGCL”), contain provisions that could have the effect of rendering more difficult, delaying, or preventing an acquisition deemed undesirable by our board of directors and therefore depress the trading price of our common stock. These provisions could also make it difficult for stockholders to take certain actions, including electing directors or taking other corporate actions, including effecting changes in our management. Among other things, our second amended and restated certificate of incorporation and amended and restated bylaws include provisions regarding:

●

a classified board of directors with three-year staggered terms, which could delay the ability of stockholders to change the membership of a majority of our board of directors;

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●

the ability of our board of directors to issue shares of preferred stock, including “blank check” preferred stock and to determine the price and other terms of those shares, including preferences and voting rights, without stockholder approval, which could be used to significantly dilute the ownership of a hostile acquirer;

●

the limitation of the liability of, and the indemnification of, our directors and officers;

●

the exclusive right of our board of directors to elect a director to fill a vacancy created by the expansion of our board of directors or the resignation, death or removal of a director, which prevents stockholders from being able to fill vacancies on our board of directors;

●

the requirement that directors may only be removed from our board of directors for cause;

●

a prohibition on stockholder action by written consent, which forces stockholder action to be taken at an annual or special meeting of stockholders and could delay the ability of stockholders to force consideration of a stockholder proposal or to take action, including the removal of directors;

●

the requirement that a special meeting of stockholders may be called only by our board of directors, the chairperson of our board of directors, our chief executive officer or our president (in the absence of a chief executive officer), which could delay the ability of stockholders to force consideration of a proposal or to take action, including the removal of directors;

●

controlling the procedures for the conduct and scheduling of board of directors and stockholder meetings;

●

the requirement for the affirmative vote of holders of at least 65% of the voting power of all of the then outstanding shares of the voting stock, voting together as a single class, to amend, alter, change or repeal any provision of the second amended and restated certificate of incorporation or amended and restated bylaws, which could preclude stockholders from bringing matters before annual or special meetings of stockholders and delay changes in our board of directors and also may inhibit the ability of an acquirer to effect such amendments to facilitate an unsolicited takeover attempt;

●

the ability of our board of directors to amend the amended and restated bylaws, which may allow our board of directors to take additional actions to prevent an unsolicited takeover and inhibit the ability of an acquirer to amend the amended and restated bylaws to facilitate an unsolicited takeover attempt; and

●

advance notice procedures with which stockholders must comply to nominate candidates to our board of directors or to propose matters to be acted upon at a stockholders’ meeting, which could preclude stockholders from bringing matters before annual or special meetings of stockholders and delay changes in our board of directors and also may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of surviving entity.

These provisions, alone or together, could delay or prevent hostile takeovers and changes in control or changes in our board of directors or management.

In addition, as a Delaware corporation, we will be subject to provisions of Delaware law, including Section 203 of the DGCL, which may generally prohibit certain stockholders holding 15% or more of our outstanding capital stock from engaging in certain business combinations with us for a specified period of time unless certain conditions are met.

Any provision of the second amended and restated certificate of incorporation, amended and restated bylaws or Delaware law that has the effect of delaying or preventing a change in control could limit the opportunity for stockholders to receive a premium for their shares of our capital stock and could also affect the price that some investors are willing to pay for our common stock.

The second amended and restated certificate of incorporation designate a state or federal court located within the State of Delaware as the exclusive forum for substantially all disputes between us and our stockholders, and also provide that the federal district courts will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act, each of which could limit the ability of our stockholders to choose the judicial forum for disputes with us or our directors, officers, or employees.26

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Our second amended and restated certificate of incorporation designates a state or federal court located within the State of Delaware as the exclusive forum for substantially all disputes between us and our stockholders, and also provide that the federal district courts will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act, each of which could limit the ability of our stockholders to choose the judicial forum for disputes with us or our directors, officers, or employees.

The second amended and restated certificate of incorporation provides that, unless we consent in writing to the selection of an alternative forum, the sole and exclusive forum for (1) any derivative action or proceeding brought on its behalf, (2) any action asserting a claim of breach of a fiduciary duty owed by any of its directors, officers, or other employees to us or our stockholders, (3) any action arising pursuant to any provision of the Delaware General Corporation Law, or the second amended and restated certificate of incorporation or the amended and restated bylaws or (4) any other action asserting a claim that is governed by the internal affairs doctrine shall be the Court of Chancery of the State of Delaware (or, if the Court of Chancery does not have jurisdiction, the federal district court for the District of Delaware), in all cases subject to the court having jurisdiction over indispensable parties named as defendants. The second amended and restated certificate of incorporation also provides that the federal district courts of the U.S. will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act. The exclusive forum provision is applicable to the fullest extent permitted by applicable law, subject to certain exceptions. Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. As a result, the exclusive forum provision will not apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. We note, however, that there is uncertainty as to whether a court would enforce this provision and that investors cannot waive compliance with the federal securities laws and the rules and regulations thereunder. Section 22 of the Securities Act creates concurrent jurisdiction for state and federal courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder.

Any person or entity purchasing or otherwise acquiring any interest in any of our securities shall be deemed to have notice of and consented to this provision. This exclusive-forum provision may limit a stockholder’s ability to bring a claim in a judicial forum of its choosing for disputes with us or our directors, officers, or other employees, which may discourage lawsuits against us and our directors, officers, and other employees. If a court were to find the exclusive-forum provision be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving the dispute in other jurisdictions, which could harm its results of operations.

We may be required to take write-downs or write-offs, restructuring and impairment or other charges that could have a significant negative effect on our financial condition, results of operations and stock price, which could cause you to lose some or all of your investment.

Although we conducted due diligence on Advent, we cannot assure you that this diligence revealed all material issues that may be present in Advent’s business, that it would be possible to uncover all material issues through a customary amount of due diligence, or that factors outside of our control will not later arise. As a result, the company

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may be forced to later write-down or write-off assets, restructure our operations, or incur impairment or other charges that could result in losses. Even if the due diligence successfully identified certain risks, unexpected risks may arise and previously known risks may materialize in a manner not consistent with our preliminary risk analysis. Even though these charges may be non-cash items and not have an immediate impact on our liquidity, the fact that the company reports charges of this nature could contribute to negative market perceptions about the Company or our securities. Accordingly, our stockholders could suffer a reduction in the value of their shares. Such stockholders are unlikely to have a remedy for such reduction in value unless they are able to successfully claim that the reduction was due to the breach by our officers or directors of a duty of care or other fiduciary duty owed to them, or if they are able to successfully bring a private claim under securities laws that the Proxy Statement / Prospectus relating to the business combination contained an actionable material misstatement or material omission.

An active market for our securities may not develop, which would adversely affect the liquidity and price of our securities.

The price of our securities may vary significantly due to factors specific to our business as well as to general market or economic conditions. Furthermore, an active trading market for our securities may never develop or, if developed, it may not be sustained. You may be unable to sell your securities unless a market can be established and sustained.

NASDAQ may delist our securities from trading on its exchange, which could limit investors’ ability to make transactions in our securities and subject us to additional trading restrictions.

Our securities are currently listed on Nasdaq. However, we cannot assure you that our securities will continue to be listed on Nasdaq in the future. In order to continue listing its securities on Nasdaq, we must maintain certain financial, distribution and stock price levels. Generally, we must maintain a minimum amount in stockholders’ equity (generally $2,500,000) and a minimum number of holders of its securities (generally 300 public holders). Additionally, we are required to demonstrate compliance with Nasdaq’s listing requirements, which are more rigorous than Nasdaq’s continued listing requirements, in order to continue to maintain the listing of our securities on Nasdaq. For instance, our stock price would generally be required to be at least $4 per share and its stockholders’ equity would generally be required to be at least $5 million and we will be required to have a minimum of 300 public holders. We cannot assure you that we will be able to meet those initial listing requirements at all times.

If Nasdaq delists our securities from trading on its exchange and we are not able to list our securities on another national securities exchange, we expect our securities could be quoted on an over-the-counter market. If this were to occur, we could face significant material adverse consequences, including:

• a limited availability of market quotations for its securities;

• reduced liquidity for its securities;

• a determination that our common stock is a “penny stock” which will require brokers trading in the common stock to adhere to more stringent rules and possibly result in a reduced level of trading activity in the secondary trading market for our securities;

• a limited amount of news and analyst coverage; and

• a decreased ability to issue additional securities or obtain additional financing in the future.

Our common stock price may change significantly and you could lose all or part of your investment as a result.

The trading price of our common stock is likely to be volatile. The stock market recently has experienced extreme volatility. This volatility often has been unrelated or disproportionate to the operating performance of particular companies. You may not be able to resell your shares of our common stock at an attractive price due to a number of factors such as those listed in “Risk Factors Relating to Our Operations and Business” and the following:

•● results of operations that vary from the expectations of securities analysts and investors;

~~• results of operations that vary from our competitors;~~27

•Table ~~changes~~of ~~in expectations as to our future financial performance, including financial estimates and investment recommendations by securities analysts and investors;~~Contents

23 ● results of operations that vary from our competitors;

~~TABLE~~● OFchanges ~~CONTENTS~~in expectations as to our future financial performance, including financial estimates and investment recommendations by securities analysts and investors;

•● declines in the market prices of stocks generally;

•● strategic actions by us or our competitors;

•● announcements by us or our competitors of significant contracts, acquisitions, joint ventures, other strategic relationships or capital commitments;

•● any significant change in our management;

•● changes in general economic or market conditions or trends in our industry or markets;

•● changes in business or regulatory conditions, including new laws or regulations or new interpretations of existing laws or regulations applicable to our business;

•● future sales of our common stock or other securities;

•● investor perceptions of the investment opportunity associated with our common stock relative to other investment alternatives;

•● the public’s response to press releases or other public announcements by us or third parties, including our filings with the SEC;

•● litigation involving us, our industry, or both, or investigations by regulators into our operations or those of our competitors;

•● guidance, if any, that we provide to the public, any changes in this guidance or our failure to meet this guidance;

•● the development and sustainability of an active trading market for our common stock;

•● actions by institutional or activist stockholders;

•● changes in accounting standards, policies, guidelines, interpretations or principles; and

•● other events or factors, including those resulting from pandemics, natural disasters, war, acts of terrorism or responses to these events.

These broad market and industry fluctuations may adversely affect the market price of our common stock, regardless of our actual operating performance. In addition, price volatility may be greater if the public float and trading volume of our common stock is low.

In the past, following periods of market volatility, stockholders have instituted securities class action litigation. If we were involved in securities litigation, it could have a substantial cost and divert resources and the attention of executive management from our business regardless of the outcome of such litigation.

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Because there are no current plans to pay cash dividends on our common stock for the foreseeable future, you may not receive any return on investment unless you sell your common stock at a price greater than what you paid for it.

We intend to retain future earnings, if any, for future operations, expansion and debt repayment and there are no current plans to pay any cash dividends for the foreseeable future. The declaration, amount and payment of any future dividends on shares of common stock will be at the sole discretion of the board of directors. The board of directors may take into account general and economic conditions, our financial condition and results of operations, our available cash and current and anticipated cash needs, capital requirements, contractual, legal, tax and regulatory restrictions, implications of the payment of dividends by us to our stockholders or by its subsidiaries to it and such other factors as the board of directors may deem relevant. As a result, you may not receive any return on an investment in our common stock unless you sell your common stock for a price greater than that which you paid for it.

Our stockholders may experience dilution in the future.

The percentage of shares of our common stock owned by current stockholders may be diluted in the future because of equity issuances for acquisitions, capital market transactions or otherwise, including, without limitation, equity awards that we may grant to its directors, officers and employees, or exercise of warrants. Such issuances may have a dilutive effect on our earnings per share, which could adversely affect the market price of our common stock.

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If securities or industry analysts do not publish research or reports about our business, if they change their recommendations regarding our common stock or if our operating results do not meet their expectations, our common stock price and trading volume could decline.

The trading market for our common stock will depend in part on the research and reports that securities or industry analysts publish about us or our businesses. If no securities or industry analysts commence coverage of us or our business, the trading price for our common stock could be negatively impacted. In the event securities or industry analysts initiate coverage, if one or more of the analysts who cover us downgrade our securities or publish unfavorable research about our businesses, or if our operating results do not meet analyst expectations, the trading price of our common stock would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, demand for our common stock could decrease, which might cause our common stock price and trading volume to decline.

Future sales, or the perception of future sales, by us or our stockholders in the public market could cause the market price for our common stock to decline.

The sale of shares of our common stock in the public market, or the perception that such sales could occur, could harm the prevailing market price of shares of our common stock. These sales, or the possibility that these sales may occur, also might make it more difficult for us to sell equity securities in the future at a time and at a price that it deems appropriate.

As of March 31, 2022, we have a total of 51,253,591 shares of our common stock outstanding. All shares held by public stockholders prior to the Business Combination and all of the shares issued in the Business Combination to former Old Advent stockholders are freely tradable without registration under the Securities Act, and without restriction by persons other than our “affiliates” (as defined under Rule 144 of the Securities Act, “Rule 144”), including our directors, executive officers and other affiliates.

The shares of Advent’s common stock reserved for future issuance under the 2021 Equity Incentive Plan will become eligible for sale in the public market once those shares are issued, subject to any applicable vesting requirements, lockup agreements and other restrictions imposed by law. A total of 6,915,892 shares of common stock have been reserved for future issuance under the 2021 Equity Incentive Plan. We filed a registration statement on Form S-8 on June 10, 2021, which covers the 6,915,892 shares of our common stock reserved under the 2021 Equity Incentive Plan. We are expected to file one or more registration statements on Form S-8 under the Securities Act to register shares of our common stock or securities convertible into or exchangeable for shares of our common stock issued pursuant to the Equity Incentive Plan. Any such Form S-8 registration statements will automatically become effective upon filing. Accordingly, shares registered under such registration statements will be available for sale in the open market.

In the future, we may also issue our securities in connection with investments or acquisitions. The amount of shares of our common stock issued in connection with an investment or acquisition could constitute a material portion of the then-outstanding shares of our common stock. Any issuance of additional securities in connection with investments or acquisitions may result in additional dilution to our stockholders.

As a public company, we are subject to additional laws, regulations and stock exchange listing standards, which impose additional costs on us and may strain our resources and divert our management’s attention.

Advent previously operated on a private basis and following the Business Combination it became a wholly-owned subsidiary of a public company that is subject to the reporting requirements of the Exchange Act, the Sarbanes-Oxley Act, the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, the listing requirements of Nasdaq and other applicable securities laws and regulations. Compliance with these laws and regulations will increase our legal and financial compliance costs and make some activities more difficult, time-consuming or costly, which may strain our resources or divert management’s attention.

We are an emerging growth company within the meaning of the Securities Act, and if we take advantage of certain exemptions from disclosure requirements available to emerging growth companies, this could make our securities less attractive to investors and may make it more difficult to compare our performance with other public companies.

We are an “emerging growth company” within the meaning of the Securities Act, as modified by the JOBS Act. We may continue to take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies including, but not limited to, not being required to

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comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act, reduced disclosure obligations regarding executive compensation in periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. As a result, our stockholders may not have access to certain information they may deem important. We cannot predict whether investors will find securities issued by us less attractive because we will rely on these exemptions. If some investors find those securities less attractive as a result of its reliance on these exemptions, the trading prices of our securities may be lower than they otherwise would be, there may be a less active trading market for our securities and the trading prices of our securities may be more volatile.

Further, Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such election to opt out is irrevocable. We have elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, we, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of our financial statements with another public company that is neither an emerging growth company nor an emerging growth company that has opted out of using the extended transition period difficult or impossible because of the potential differences in accountant standards used.

We may redeem unexpired public warrants prior to their exercise at a time that is disadvantageous for warrant holders.

We will have the ability to redeem outstanding public warrants at any time after they become exercisable and prior to their expiration, at a price of $0.01 per warrant, provided that the last reported sales price of our common stock equals or exceeds $18540.00 per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading days within a 30 trading-day period ending on the third trading day prior to the date we send the notice of redemption to the warrant holders. If and when the public warrants become redeemable by us, we may exercise our redemption right when the registration statement to which this prospectus forms a part comes into effect with respect to the shares of common stock underlying such warrants. Redemption of the ~~outstanding~~ outstanding public warrants could force you to: (1) exercise your warrants and pay the related exercise price at a time when it may be disadvantageous for you to do so; (2) sell your warrants at the then-current market price when you might otherwise wish to hold your warrants; or (3) accept the nominal redemption price which, at the time the outstanding public warrants are called for redemption, is likely to be substantially less than the market value of your warrants. None of the placement warrants or working capital warrants will be redeemable by us for cash so long as they are held by our sponsor or its permitted transferees.

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Changes in accounting standards and subjective assumptions, estimates and judgments by management related to complex accounting matters could significantly affect our financial condition and results of operations.

Accounting principles and related pronouncements, implementation guidelines and interpretations we apply to a wide range of matters that are relevant to our business, including, but not limited to, revenue recognition, leases and stock-based compensation, are complex and involve subjective assumptions, estimates and judgments by our management. Changes in accounting pronouncements or their interpretation or changes in underlying assumptions, estimates or judgments by our management could significantly change our reported or expected financial performance.

The exercise of Warrants for our common stock would increase the number of shares eligible for future resale in the public market and result in dilution to our stockholders.

As of ~~March 31~~August 14, ~~2022~~2025, we had Warrants to purchase an aggregate of 26 878,~~369,557~~985 shares of our common stock outstanding. To the extent remaining Warrants are exercised, additional shares of common stock will be issued, which will result in dilution to the then-existing holders of common stock and increase the number of shares eligible for resale in the public market. Sales of substantial numbers of such shares in the public market or the fact that such Warrants may be exercised could adversely affect the market price of our common stock.

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The valuation of our Warrants could increase the volatility in our net income (loss) in our consolidated statements of earnings (loss).

The change in fair value of our Warrants is the result of changes in stock price and Warrants outstanding at each reporting period. The Change in Fair Value of Warrant Liabilities represents the mark-to-market fair value adjustments to the outstanding Warrants issued in connection with the initial public offering of ACMI and the concurrent private placement. Significant changes in our stock price or number of Warrants outstanding may adversely affect our net income (loss) in our consolidated statements of earnings (loss).

27Changes in US trade policy, including the imposition of tariffs and the resulting consequences, may have a material adverse impact on our business and results of operations.

~~TABLE~~The US OFgovernment ~~CONTENTS~~has indicated its intent to adopt a new approach to trade policy and in some cases to renegotiate, or potentially terminate, certain existing bilateral or multi-lateral trade agreements. It has also initiated or is considering the imposition of tariffs on certain foreign goods. Changes in US trade policy could result in one or more U.S. trading partners adopting responsive trade policies making it more difficult or costly for us to export our products to those countries. These measures could also result in increased costs for goods imported into the United States. This in turn could require us to increase prices to our customers which may reduce demand, or, if we are unable to increase prices, result in lowering our margin on products sold.

~~USE~~We cannot OFpredict ~~PROCEEDS~~future trade policy or the terms of any renegotiated trade agreements and their impact on our business. The adoption and expansion of trade restrictions, the occurrence of a trade war, or other governmental action related to tariffs or trade agreements or policies has the potential to adversely impact demand for our products, our costs, our customers, our suppliers, and the US economy, which in turn could adversely impact our business, financial condition and results of operations.

All of the shares offered by the Selling Securityholders pursuant to this prospectus will be sold by the Selling Securityholders for their respective amounts. We will not receive any of the proceeds from these sales.

The Selling Securityholders will pay any underwriting discounts and commissions and expenses incurred by the Selling Securityholders for brokerage, accounting, tax or legal services or any other expenses incurred by the Selling Securityholders in disposing of the securities. We will bear the costs, fees and expenses incurred in effecting the registration of the securities covered by this prospectus, including all registration and filing fees, Nasdaq listing fees and fees and expenses of our counsel and our independent registered public accounting firm.

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MARKET INFORMATION FOR SECURITIES AND DIVIDEND POLICY

Market Information

Our Common Stock and Public Warrants are currently listed on the Nasdaq Capital Market under the symbols “ADN” and “ADNWW,” respectively. Prior to the consummation of the Business Combination, AMCI’s Class A Common Stock, public warrants and units were listed on the Nasdaq Stock Market under the symbols “AMCI,” “AMCIW” and “AMCIU,” respectively.

Holders

Dividend Policy

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UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

The following unaudited pro forma condensed combined financial statements are provided to aid you in your analysis of the financial aspects of the merger with AMCI Acquisition Corp. (“AMCI”) and the consummation of the PIPE Investment, effective February 4, 2021, and the acquisitions of SerEnergy A/S (“SerEnergy”) and fischer eco solutions GmbH (“FES”), effective August 31, 2021. The merger with AMCI, consummation of the PIPE Investment and acquisitions of SerEnergy and FES are collectively referred to as the “Transactions.”

The following unaudited pro forma condensed combined statements of operations are based upon the historical consolidated statements of operations of AMCI, SerEnergy and FES, after giving effect to the Transactions, and after applying the assumptions, reclassifications and adjustments described in the accompanying notes. The Transactions were consummated during 2021 and are therefore reflected in the historical audited consolidated balance sheet of Advent Technologies Holdings, Inc. as of December 31, 2021. Therefore, no unaudited pro forma condensed combined balance sheet has been presented herein. The unaudited pro forma condensed combined statements of operations for the year ended December 31, 2021 are presented as if the Transactions had occurred on January 1, 2021.

The unaudited pro forma condensed combined statements of operations should be read in conjunction with the accompanying notes thereto. In addition, the unaudited pro forma condensed combined statements of operations were based on and should be read in conjunction with:

• the audited historical consolidated financial statements and accompanying notes of Advent Technologies Holdings, Inc. for the year ended December 31, 2021, included in our Annual Report on Form 10-K filed on March 31, 2022;

• the unaudited historical financial statements of AMCI for the period from January 1, 2021 through February 4, 2021, the date of the merger;

• the unaudited historical financial statements of SerEnergy for the period from January 1, 2021 through August 31, 2021, the date of the acquisition;

• the unaudited historical financial statements of FES for the period from January 1, 2021 through August 31, 2021, the date of the acquisition.

The unaudited pro forma condensed combined statements of operations have been presented for illustrative purposes only. The pro forma information is not necessarily indicative of what our results of operations actually would have been had the Transactions been completed as of the dates indicated or that may be achieved in the future. In addition, the unaudited pro forma condensed combined statements of operations do not purport to project our future operating results. The actual results reported in periods following the Transactions may differ significantly from those reflected in these unaudited pro forma condensed combined statements of operations.

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~~UNAUDITED~~Risks Related ~~PRO~~to ~~FORMA~~Our ~~CONDENSED~~Intellectual ~~COMBINED STATEMENT OF OPERATIONS~~ Property

~~FOR~~Our ability ~~THE~~to ~~YEAR~~protect ~~ENDED~~our ~~DECEMBER~~intellectual ~~31,~~property ~~2021~~ and proprietary technology is uncertain.

~~(All~~We rely ~~amounts~~primarily inon ~~USD~~patent, ~~except~~copyright, ~~for~~trademark ~~number~~and trade secret laws, as well as confidentiality and non- disclosure agreements and other methods, to protect our proprietary technologies and know-how. As of ~~shares~~October 11, 2024, we owned 108 issued patents (38 domestic and 70 foreign), 35 pending patent applications (13 domestic and 22 foreign), 45 registered trademarks (5 domestic and 40 foreign) and 8 pending trademark applications (3 domestic and 5 foreign).

	Historical					Historical
	4(A) AMCI	4(B) Advent Technologies Holdings, Inc.	Transaction Accounting Adjustments (Note 4)		Total	4(C) SerEnergy	4(D) FES	Transaction Accounting Adjusments (Note 4)		Pro Forma Combined
Revenue, net	$—	$7,068,842	$—		$7,068,842	$29,467,465	$7,917,955	$(28,470,144)	4(d)	$15,984,118
Cost of revenues	—	(5,406,216)			(5,406,216)	(11,294,911)	(9,763,059)	13,056,755	4(d)	(13,407,431)
Gross profit / (loss)	—	1,662,626	—		1,662,626	18,172,554	(1,845,104)	(15,413,389)		2,576,687
Cost and operating expenses:
Income from grants	—	829,207	—		829,207	1,033,513	—	—		1,862,720
Research and development expenses	—	(3,540,540)	—		(3,540,540)	(3,662,878)	(3,466,461)	3,729,541	4(d)	(6,940,338)
Administrative and selling expenses	(165,942)	(41,876,741)	5,693,750	4(a), 4(b)	(36,348,933)	(2,960,818)	(1,658,577)	—		(40,968,328)
Amortization of intangibles	—	(1,184,830)	—		(1,184,830)	—	(1,543,485)	(56,515)	4(d), 4(e)	(2,784,830)
Operating costs and formation costs	—	—	—		—	—	—	—		—
Franchise tax expense	—	—	—		—	—	—	—		—
Other operating expenses	—	—	—		—	—	—	—		—
Operating profit / (loss)	(165,942)	(44,110,278)	5,693,750		(38,582,470)	12,582,371	(8,513,627)	(11,740,363)		(46,254,089)
Change in fair value of warrant liabilities	4,866,238	22,743,057	—		27,609,295	—	—	—		27,609,295
Other income - dividends and interest	69,712	—	(69,712)	4(c)	—	—	—	—		—
Finance costs	—	(51,561)	—		(51,561)	(150,187)	(474,011)	624,198	4(f)	(51,561)
Foreign exchange differences, net	—	(42,708)	—		(42,708)	—	—	—		(42,708)
Other income (expense), net	—	15,638	—		15,638	(34,454)	8,987,638	(8,987,638)	4(g)	(18,816)
Loss before income tax	4,770,008	(21,445,852)	5,624,038		(11,051,806)	12,397,730	—	(20,103,803)		(18,757,879)
Income tax	—	922,510	—		922,510	(977,866)	—	(44,141)		(99,497)
Net loss	$4,770,008	$(20,523,342)	$5,624,038		$(10,129,296)	$11,419,864	$—	$(20,147,944)		$(18,857,376)
Weighted average number of common shares outstanding, basic and diluted		45,814,868			46,128,745					51,253,591
Basic and diluted net loss per share		$(0.45)Note 5			$(0.22)Note 5					$(0.37)Note 5

We have applied for patent protection relating to certain existing and proposed products and processes. While we generally apply for patents in those countries where we intend to make, have made, use, or sell patented products, we may not accurately predict all the countries where patent protection will ultimately be desirable. If we fail to timely file a patent application in any such country, we may be precluded from doing so later. Furthermore, we cannot assure you that any of our patent applications will be approved. The rights granted to us under our patents, including prospective rights sought in our pending patent applications, may not be meaningful or provide us with any commercial advantage. In addition, those rights could be opposed, contested, or circumvented by our competitors or be declared invalid or unenforceable in judicial or administrative proceedings. The failure of our patents to adequately protect our technology might make it easier for our competitors to offer the same or similar products or technologies. Competitors may be able to design around our patents or develop products that provide outcomes which are comparable to ours without infringing on our intellectual property rights. Due to differences between foreign and U.S. patent laws, our patented intellectual property rights may not receive the same degree of protection in foreign countries as they would in the United States. Even if patents are granted outside the United States, effective enforcement in those countries may not be available. Since most of our issued patents are for the United States only, we lack a corresponding scope of patent protection in other countries. In countries where we do not have significant patent protection, we may not be able to stop a competitor from marketing products in such countries that are the same as or similar to our product.

~~See~~We plan ~~accompanying~~to ~~notes~~rely on our trademarks, trade names and brand names to distinguish our product from the ~~unaudited~~products ~~pro~~of ~~forma~~our ~~condensed~~competitors ~~combined~~and ~~financial~~have registered ~~information~~or applied to register many of these trademarks. We cannot assure you that our trademark applications will be approved. Third parties may also oppose our trademark applications, or otherwise challenge our use of the trademarks. In the event that our trademarks are successfully challenged, we could be forced to rebrand our product, which could result in loss of brand recognition, and could require us to devote resources to advertising and marketing new brands. Further, we cannot assure you that competitors will not infringe upon our trademarks, or that we will have adequate resources to enforce our trademarks.

We also rely on trade secrets, know-how, and technology, which are not protected by patents, to maintain our competitive position. We try to protect this information by entering into confidentiality and intellectual property assignment agreements with parties that develop intellectual property for us and/or have access to it, such as our officers, employees, consultants, contract manufacturers and advisors. However, in the event of unauthorized use or disclosure or other breaches of such agreements, we may not be provided with meaningful protection for our trade secrets or other proprietary information. In addition, our trade secrets may otherwise become known or be independently discovered by competitors. To the extent that our commercial partners, collaborators, employees, and consultants use intellectual property owned by others in their work for us, disputes may arise as to the rights in related or resulting know-how and inventions. If any of our trade secrets, know-how or other technologies not protected by a patent were to be disclosed to or independently developed by a competitor, our business, financial condition, and results of operations could be materially adversely affected.

In the future, we may enter into licensing agreements to maintain our competitive position. If we enter into in-bound intellectual property license agreements, we may not be able to fully protect the licensed intellectual property rights or maintain those licenses. Future licensors could retain the right to prosecute and defend the intellectual property rights licensed to us, in which case we would depend on the ability of our licensors to obtain, maintain, and enforce intellectual property protection for the licensed intellectual property. These licensors may determine not to pursue litigation against other companies or may pursue such litigation less aggressively than we would. Further, entering into such license agreements could impose various diligence, commercialization, royalty, or other obligations on us. Future licensors may allege that we have breached our license agreement with them, and accordingly seek damages or to terminate our license, which could adversely affect our competitive business position and harm our business prospects.

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~~NOTES~~If a TOcompetitor ~~UNAUDITED~~infringes ~~PRO~~upon ~~FORMA~~one ~~CONDENSED~~of ~~COMBINED~~our ~~FINANCIAL~~patents, ~~STATEMENTS~~trademarks, or other intellectual property rights, enforcing those patents, trademarks, and other rights may be difficult and time consuming. Even if successful, litigation to defend our patents and trademarks against challenges or to enforce our intellectual property rights could be expensive and time consuming and could divert management’s attention from managing our business. Moreover, we may not have sufficient resources to defend our patents or trademarks against challenges or to enforce our intellectual property rights. In addition, if third parties infringe any intellectual property that is not material to the products that we make, have made, use, or sell, it may be impractical for us to enforce this intellectual property against those third parties.

~~Note~~We may 1.need ~~Description~~to ofdefend ~~the~~ourselves ~~Transactions~~against patent or trademark infringement claims, which may be time-consuming and cause us to incur substantial costs.

~~Merger~~Companies, organizations ~~with~~or ~~AMCI~~individuals, ~~Acquisition~~including ~~Corp~~our competitors, may own or obtain patents, trademarks or other proprietary rights that would prevent or limit our ability to make, use, develop, license or sell our fuel cell and membrane technologies, which could make it more difficult for us to operate our business. We may receive inquiries from patent or trademark owners inquiring whether we infringe their proprietary rights. Companies owning patents or other intellectual property rights relating to fuel cells may allege infringement of such rights. In response to a determination that we have infringed upon a third party’s intellectual property rights, we may be required to do one or more of the following:

On● ~~October 12,~~cease ~~2020~~development, ~~AMCI~~sales, ~~Merger~~license ~~Sub~~or ~~and~~use ~~Advent Technologies, Inc. (“Advent”), entered into the original Merger Agreement, pursuant to which Merger Sub merged with and into Advent, effective as~~ of ~~February 4,~~fuel ~~2021,~~cells ~~for~~or anmembranes ~~aggregate~~that ~~value~~incorporate ~~equal to $250 million minus~~ the ~~amount~~asserted ofintellectual the Closing Net Indebtedness, with each share of New Advent common stock valued for such purposes at $10.00. Advent survived the Business Combination as a wholly owned subsidiary of AMCI, and AMCI was renamed to “Advent Technologies Holdings, Inc.”property;

~~Upon~~● ~~the~~pay ~~closing~~substantial of the Business Combination, AMCI’s certificate of incorporation was amended and restated to, among other things, authorize the issuance of 111 million shares, of which 110 million are shares of common stock, par value $0.0001 per share and 1 million shares are shares of undesignated preferred stock, par value $0.0001 per share.damages;

In● ~~connection~~obtain ~~with the execution of the Business Combination Agreement, AMCI entered into separate subscription agreement with~~ a ~~number~~license offrom ~~investors (each a “Subscriber”), pursuant to which~~ the ~~Subscribers~~owner ~~agreed to purchase, and AMCI agreed to sell to the Subscribers, an aggregate~~ of ~~6.5 million shares of common stock (~~the ~~“PIPE~~asserted ~~Shares”),~~intellectual ~~for~~property ~~a purchase price of $10.00 per share and an aggregate purchase price of $65.0 million~~right, inwhich alicense ~~private~~may ~~placement~~not ~~pursuant~~be toavailable ~~the~~on ~~subscription~~reasonable ~~agreements~~terms ~~(the~~or ~~“PIPE~~at ~~Investment”).~~all; ~~The PIPE Investment closed simultaneously with the consummation of the Business Combination.~~or

~~References~~● toredesign ~~Merger~~one ~~Agreement~~or ~~are~~more ~~construed~~aspects toor ~~refer~~systems to the Merger Agreement noted above as amended on October 19, 2020 to remove the requirement for AMCI to cash-out all outstanding Warrants and as amended again on December 31, 2020 to (a) reduce the size of ~~the~~our ~~board~~fuel ofcells ~~directors~~or of the Combined Entity following the Business Combination from nine members to seven members, (b) increase the amount of aggregate cash bonus payments to be made in connection with Closing from $3membranes.~~0 million to $5.0 million, and (c) amend certain terms of the form of employment agreement of Christos Kaskavelis.~~

~~After~~A successful ~~giving~~claim ~~effect~~of toinfringement ~~the~~against ~~redemption~~us ofcould ~~the~~materially ~~Class A~~adversely ~~public~~affect ~~shares~~our business, ~~Advent’s~~ ~~shareholders~~prospects, ~~hold~~operating ~~25.0 million~~results ~~shares~~and offinancial condition. ~~AMCI~~Any ~~common~~litigation ~~stock~~or ~~immediately~~claims, ~~after~~whether ~~the~~valid ~~Closing~~or invalid, ~~which~~could ~~approximates~~result ain ~~54%~~substantial ~~ownership~~costs ~~level~~and diversion of resources.

Stockholder	%	No. shares
Advent	54.3	25,033,398
Public	19.6	9,059,530
Sponsor	5.4	2,474,009
AMCI’s executive management	1.1	485,000
Other AMCI holders	5.5	2,554,010
PIPE Investors	14.1	6,500,000
Total	100%	46,105,947

~~The foregoing ownership percentages with respect to the Combined~~Our ~~Entity~~business ~~following~~may ~~the~~be ~~Business~~adversely ~~Combination~~affected ~~reflect~~if ~~that~~we ~~(i) there~~ are nounable ~~adjustments~~to ~~for~~protect ~~the~~our ~~outstanding~~intellectual ~~public,~~property ~~private~~rights ~~placement~~from orunauthorized ~~working~~use ~~capital warrants issued~~ by ~~AMCI;~~third ~~(ii) Advent’s Closing Net Indebtedness was ($0~~parties.3 million), computed as debt less cash and cash equivalents, immediately prior to the Closing; (iii) no awards were issued under the Equity Incentive Plan, and (iv) AMCI did not engage in any kind of equity financing prior to the Closing, other than the $65.0 million PIPE investment described above.

~~Acquisitions~~Failure to adequately protect our intellectual property rights could result in our competitors offering similar products, potentially resulting in the loss of ~~SerEnergy~~some ~~A/S~~of our competitive advantage and ~~fischer~~a ~~eco~~decrease in our revenue, which would adversely affect our business, prospects, ~~solutions~~financial ~~GmbH~~condition and operating results. Our success depends, at least in part, on our ability to protect our core technology and intellectual property. To accomplish this, we will rely on a combination of patents, trade secrets (including know-how), employee and third-party nondisclosure agreements, copyright, trademarks, intellectual property licenses and other contractual rights to establish and protect our rights in our technology.

~~On June 25, 2021, the Company entered into a Share Purchase~~The ~~Agreement~~protection ~~with F.E.R. Fischer Edelstahlrohre GmbH (the “Seller), effective as~~ of ~~August 31,~~our ~~2021,~~intellectual ~~which~~property ~~provided~~rights ~~for~~will ~~the~~be ~~Company~~important to ~~acquire~~our ~~all~~future ofbusiness ~~the issued and outstanding equity interests in SerEnergy and FES, two wholly-owned subsidiaries of the Seller, together with certain outstanding shareholder loan receivables~~opportunities. ~~Pursuant to the Share Purchase Agreement~~However, the ~~Company~~measures ~~acquired~~we ~~SerEnergy and FES, the fuel cell systems business of fischer Group. SerEnergy is a manufacturer of~~take ~~methanol-powered~~to ~~high-temperature~~protect ~~polymer~~our ~~electrolyte~~intellectual ~~membrane~~property ~~(“HT-PEM”)~~from ~~fuel~~unauthorized ~~cells~~use ~~and~~by ~~operates~~others ~~facilities~~may innot ~~Aalborg,~~be ~~Denmark~~effective ~~and~~for invarious ~~Manila~~reasons, ~~Philippines.~~including ~~FES provides fuel-cell stack assembly and testing as well as~~ the ~~production of critical fuel cell components of the SerEnergy HT-PEM fuel cells, including membrane electrode assemblies, bipolar plates and reformers.~~following:

●

any patent applications we submit may not result in the issuance of patents;

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As● ~~consideration for~~ the ~~transactions~~scope ~~contemplated by the Share Purchase Agreement, the Company paid to the Seller $17.9 million in cash and on August 31, 2021, the Company issued to the Seller 5.1 million shares~~ of ~~common~~our stock of the Company with a par value $0.0001 per share (the “Share Consideration”). The Share Consideration was capped to shares representing 9.999% of the Company’s common stock outstanding as of the completion (taking into account the common stock issued aspatents ~~the~~may ~~Share~~not ~~Consideration, the “Cap”). An additional amount of $4.4 million, representing cash on the balance sheet of the acquired businesses at closing, will~~ be ~~paid~~broad toenough ~~F.E.R. fischer Edelstahlrohre GmbH~~ to ~~complete~~protect ~~the~~our ~~acquisition~~proprietary ~~of SerEnergy and FES.~~rights;

~~The~~● ~~merger~~our ~~with~~issued ~~AMCI,~~patents ~~consummation~~may ofbe ~~the~~challenged ~~PIPE Investment~~ and/or ~~the acquisitions~~invalidated ofby ~~SerEnergy~~our ~~and FES are collectively referred to as the “Transactions.”~~competitors;

~~Note~~● 2.the ~~Basis~~costs ofassociated ~~Presentation~~with enforcing patents, confidentiality and invention agreements or other intellectual property rights may make aggressive enforcement impracticable;

~~The~~● ~~unaudited~~current pro forma condensed combined financial statements were prepared in accordance with Article 11 of SEC Regulation S-X, as amended by the final rule, Release No. 33-10786 “Amendments to Financial Disclosures about Acquired and ~~Disposed~~future ~~Businesses.”~~competitors ~~Release~~may ~~No.~~circumvent ~~33-10786~~our ~~replaces~~patents; ~~the existing pro forma adjustment criteria with simplified requirements to depict the accounting for the transaction (“Transaction Accounting Adjustments”)~~ and present the reasonably estimable synergies and other transaction effects that have occurred or are reasonably expected to occur (“Management’s Adjustments”). We have elected not to present Management’s Adjustments and are only presenting Transaction Accounting Adjustments in the unaudited pro forma condensed combined financial information. The adjustments presented in the unaudited pro forma condensed combined financial statements have been identified and presented to provide relevant information necessary for an understanding of the combined company.

~~The~~● ~~unaudited~~our ~~pro~~in-licensed ~~forma~~patents ~~condensed~~may ~~combined~~be ~~statements of operations are based upon the historical consolidated statements of operations of AMCI~~invalidated, ~~SerEnergy~~or ~~and FES, after giving effect to~~ the ~~Transactions,~~owners and after applying the assumptions, reclassifications and adjustments described in the accompanying notes. The Transactions were consummated during 2021 and are therefore reflected in the historical audited consolidated balance sheet of ~~Advent~~these ~~Technologies~~patents ~~Holdings,~~may ~~Inc.~~breach asour oflicense ~~December 31, 2021~~arrangements. Therefore, no unaudited pro forma condensed combined balance sheet has been presented herein. The unaudited pro forma condensed combined statements of operations for the year ended December 31, 2021 are presented as if the Transactions had occurred on January 1, 2021.

~~The~~Patent, trademark, ~~unaudited~~and ~~pro~~trade ~~forma~~secret ~~condensed~~laws ~~combined~~vary ~~statements~~significantly ofthroughout ~~operations~~the world. Some foreign countries do not protect intellectual property ~~should~~rights beto ~~read~~the insame ~~conjunction~~extent ~~with~~as do the ~~accompanying~~laws ~~notes~~of ~~thereto~~the U.S. ~~In addition~~Further, policing the ~~unaudited~~unauthorized ~~pro~~use ~~forma~~of ~~condensed~~our ~~combined~~intellectual ~~statements~~property ofin ~~operations~~foreign ~~were~~jurisdictions may ~~based~~be ondifficult. ~~and~~Therefore, ~~should~~our intellectual property rights may not be ~~read~~as instrong ~~conjunction~~or ~~with:~~as easily enforced outside of the U.S.

•Our patent ~~the~~applications ~~audited~~may ~~historical~~not ~~consolidated~~issue ~~financial~~as ~~statements and accompanying notes of Advent Technologies Holdings~~patents, ~~Inc.~~which ~~for~~may ~~the~~have ~~year~~a ~~ended~~material ~~December~~adverse ~~31,~~effect ~~2021,~~on ~~included in~~ our ~~Annual~~ability ~~Report~~to onprevent ~~Form~~others ~~10-K~~from ~~filed~~commercially exploiting onproducts ~~March~~similar ~~31,~~to ~~2022;~~ours.

•We cannot ~~the~~be ~~unaudited~~certain ~~historical~~that ~~financial~~we ~~statements~~are ofthe ~~AMCI~~first ~~for~~inventor of the ~~period~~subject ~~from~~matter ~~January~~to 1which we have filed a particular patent application, ~~2021~~or ~~through~~if we ~~February~~are 4the first party to file such a patent application. If another party has filed a patent application to the same subject matter as we have, ~~2021~~we may not be entitled to the protection sought by the patent application. Further, the ~~date~~scope of protection of issued patent claims is often difficult to determine. As a result, we cannot be certain that the ~~merger;~~patent applications that we file will issue, or that our issued patents will afford protection against competitors with similar technology. In addition, our competitors may design around our issued patents, which may adversely affect our business, prospects, financial condition or operating results.

•We may ~~the~~not ~~unaudited~~be ~~historical~~able ~~financial~~to ~~statements~~protect ofour ~~SerEnergy~~intellectual ~~for~~property ~~the~~rights ~~period~~throughout ~~from January 1, 2021 through August 31, 2021,~~ the ~~date of the acquisition;~~world.

•Filing, prosecuting, ~~the~~and ~~unaudited~~defending ~~historical~~patents ~~financial~~on ~~statements~~product ofcandidates ~~FES~~in ~~for~~all countries throughout the ~~period~~world ~~from~~would ~~January~~be 1prohibitively expensive, ~~2021~~and our ~~through~~intellectual ~~August~~property ~~31,~~rights ~~2021,~~in some countries outside the ~~date~~U.S. can be less extensive than those in the U.S. In addition, the laws of some foreign countries do not protect intellectual property rights to the ~~acquisition~~same extent as federal and state laws in the U.S. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and may also export otherwise infringing products to territories where we have patent protection, but enforcement is not as strong as that in the U.S. These products may compete with our product and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

~~Management~~Many companies ~~will~~have ~~perform~~encountered asignificant ~~comprehensive~~problems ~~review~~in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the ~~accounting policies~~enforcement of ~~SerEnergy~~patents, trade secrets and ~~FES.~~other Asintellectual aproperty ~~result~~protection, ofparticularly ~~the~~those ~~review~~relating to emerging technologies, ~~management~~which ~~may~~could ~~identify~~make ~~differences~~it ~~between~~difficult for us to stop the ~~accounting~~infringement ~~policies~~of our patents or marketing of ~~the~~competing ~~Company~~products ~~and~~in ~~SerEnergy~~violation ~~and~~of ~~FES~~our proprietary rights generally. Proceedings to enforce our patent rights in foreign jurisdictions, ~~which~~whether or not successful, ~~when~~could ~~conformed~~result in substantial costs and divert our efforts and attention from other aspects of our business, could ~~have~~put aour ~~material~~patents ~~impact~~at onrisk ~~the~~of ~~consolidated~~being ~~financial~~invalidated or interpreted narrowly and our ~~statements~~patent applications at risk of ~~the~~not ~~Company.~~issuing ~~Based~~and oncould anprovoke ~~initial~~third ~~analysis,~~parties ~~management~~to ~~did~~assert claims against us. We may not ~~identify~~prevail in any ~~differences~~ lawsuits that ~~would~~we ~~have~~initiate, aand ~~material~~the ~~impact~~damages onor ~~the~~other ~~unaudited~~remedies ~~pro~~awarded, ~~forma~~if ~~condensed~~any, ~~combined~~may ~~financial~~not ~~information.~~be Ascommercially ameaningful. ~~result~~Accordingly, our efforts to enforce our intellectual property rights around the ~~unaudited~~world ~~pro~~may ~~forma condensed~~be ~~combined~~inadequate ~~financial~~to ~~information~~obtain ~~does~~a ~~not~~significant ~~assume~~commercial ~~any~~advantage ~~differences~~from inthe ~~accounting~~intellectual property ~~policies~~that we develop or license.

AMCI and Advent Technologies Inc. have not had any historical relationship prior to the merger. Additionally, SerEnergy and FES have not had any historical relationship with Advent Technologies Holdings, Inc. prior to the

~~TABLE~~Table OFof ~~CONTENTS~~Contents

~~acquisitions.~~If we ~~Accordingly,~~are nounable ~~pro forma adjustments were required~~ to ~~eliminate activities~~protect ~~between~~the ~~Advent~~confidentiality ~~Technologies~~of ~~Inc.~~our ~~and~~trade ~~these entities. However~~secrets, ~~there~~our ~~were~~business ~~transactions between SerEnergy~~ and ~~FES~~competitive ~~prior~~position tocould ~~the~~be ~~acquisitions~~harmed. ~~As such, management has included pro forma adjustments to eliminate the transactions between SerEnergy and FES.~~

~~The~~In addition ~~pro~~to ~~forma~~patent ~~adjustments~~protection, ~~reflecting~~we ~~the~~also ~~consummation~~rely ofupon ~~the~~copyright and trade secret protection, as well as non-disclosure agreements and invention ~~Transactions~~assignment ~~are~~agreements ~~based~~with onour ~~certain~~employees, ~~currently~~consultants, ~~available~~contract ~~information~~manufacturers and ~~certain~~third ~~assumptions~~parties, to protect our confidential and ~~methodologies~~proprietary information. ~~that~~In ~~Management~~addition ~~believes~~to ~~are~~contractual ~~reasonable~~measures, ~~under~~we try to protect the ~~circumstances~~confidential nature of our proprietary information using commonly accepted physical and technological security measures. ~~The~~Such ~~unaudited~~measures ~~condensed~~may ~~pro~~not, ~~forma~~for ~~adjustments~~example, ~~which~~in ~~are~~the ~~described~~case inof misappropriation of a trade ~~these~~secret ~~accompanying~~by ~~notes~~an employee or third party with authorized access, ~~may~~provide beadequate ~~revised~~protection asfor ~~additional~~our proprietary information. ~~becomes~~Our ~~available~~security measures ~~and~~may isnot ~~evaluated.~~prevent ~~Therefore,~~an itemployee isor ~~likely~~consultant ~~that~~from ~~the~~misappropriating ~~actual~~our ~~adjustments~~trade ~~will~~secrets ~~differ~~and ~~from~~providing ~~the~~them ~~pro~~to ~~forma~~a ~~adjustments~~competitor, and itrecourse we istake ~~possible~~against ~~the~~such ~~difference~~misconduct may benot provide an adequate remedy to protect our interests fully. Unauthorized parties may also attempt ~~material~~to copy or reverse engineer certain aspects of our product that we consider proprietary. ~~Management~~Enforcing ~~believes~~a claim that ~~its~~a ~~assumptions~~party ~~and~~illegally ~~methodologies~~disclosed or ~~provide~~misappropriated a ~~reasonable~~trade ~~basis~~secret ~~for~~can ~~presenting~~be ~~all~~difficult, ofexpensive, and time-consuming, and the ~~significant~~outcome ~~effects~~is ofunpredictable. ~~the~~Even ~~Transactions~~though ~~based~~we onuse commonly ~~information~~accepted ~~available~~security tomeasures, ~~Management~~trade atsecret ~~the~~violations ~~time~~are ~~and~~often ~~that~~a matter of state law, and the ~~pro~~criteria ~~forma~~for protection of trade ~~adjustments~~secrets ~~give~~can ~~appropriate~~vary ~~effect~~among todifferent ~~those~~jurisdictions. ~~assumptions~~In ~~and~~addition, ~~are~~trade ~~properly~~secrets ~~applied~~may be independently developed by others in ~~the~~a ~~unaudited~~manner ~~pro~~that could ~~forma~~prevent ~~condensed~~legal ~~combined~~recourse ~~financial~~by us. If any of our confidential or proprietary information, such as our trade secrets, were to be disclosed or misappropriated, or if any such information was independently developed by a competitor, our business and competitive position could be harmed.

~~The unaudited pro forma condensed combined financial information has~~Third ~~been~~parties ~~prepared~~may ~~for~~assert ~~informational~~that ~~purposes~~our ~~only~~employees toor ~~illustrate~~consultants ~~the effect of the Transactions and is not necessarily indicative of what the actual results of operations would~~ have ~~been~~wrongfully ~~had~~used ~~the~~or ~~Transactions~~disclosed ~~taken~~confidential ~~place~~information onor ~~the~~misappropriated ~~dates indicated, nor are~~trade ~~they indicative of the future consolidated results of operations of the combined company~~secrets. ~~They should be read in conjunction with the historical financial statements and notes thereto as discussed above.~~

~~Note~~We employ 3individuals who previously worked with other companies, including our competitors or potential competitors. ~~Accounting~~Although ~~Treatment~~we try to ensure that our employees and consultants do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise used or disclosed intellectual property, including trade secrets or other proprietary information, of a former employer or other third party. Litigation may be necessary to defend against these claims. If we fail in defending any such claims or settling those claims, in addition to paying monetary damages or a settlement payment, we may lose valuable intellectual property rights or personnel. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Merger with AMCI Acquisition Corp

Notwithstanding the legal form of the merger with AMCI, the merger was accounted for as a reverse recapitalization, with no goodwill or other intangible assets recorded, in accordance with U.S. GAAP. Under this method of accounting, AMCI was treated as the “acquired” company for financial reporting purposes. Accordingly, for accounting purposes, the merger with AMCI was treated as the equivalent of Advent issuing stock for the net assets of AMCI, accompanied by a recapitalization. Advent was determined to be the accounting acquirer based on evaluation of the following facts and circumstances:

• Advent’s stockholders have the greatest voting interest in the Combined Entity with 54.3% voting interest;

• the largest individual minority stockholder of the Combined Entity was a stockholder of Advent;

• Advent’s appointed directors represent five out of seven board seats for the Combined Entity’s board of directors;

• Advent selects all senior management (executives) of the Combined Entity;

• Advent’s senior management comprise the majority of the senior management of the Combined Entity;

• Advent operations are the only continuing operations of the Combined Entity.

Acquisitions of SerEnergy A/S and fischer eco solutions GmbH

The acquisitions of SerEnergy and FES were accounted for as business combinations in accordance with Accounting Standards Codification (“ASC”) Topic 805, Business Combinations (“ASC 805”). Management used its best estimates and assumptions to allocate fair values to the tangible and identifiable intangible assets acquired and liabilities assumed and related income tax impacts as of the acquisition date. Goodwill as of the acquisition date was measured as the excess of purchase consideration over the fair value of net tangible and identifiable intangible assets acquired.

Note 4. Adjustments to Unaudited Pro Forma Condensed Combined Statement of Operations for the Year Ended December 31, 2021

The pro forma notes and transaction accounting adjustments are as follows:

Pro forma notes

(A) Derived from the unaudited statement of operations of AMCI for the period from January 1, 2021 to February 4, 2021.

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~~(B)~~CAUTIONARY STATEMENT ~~Derived~~REGARDING ~~from~~FORWARD-LOOKING ~~the audited statement of operations of Advent Technologies Holdings, Inc. for the year ended December 31, 2021.~~STATEMENTS

~~(C)~~This prospectus ~~Derived~~and ~~from~~ the ~~unaudited~~information ~~statement~~incorporated herein by reference may constitute “forward-looking statements”, which reflect our current views with respect to, among other things, our operations and financial performance. All statements other than statements of historical facts contained in this prospectus, including statements regarding our future results of operations and financial position, business strategy and plans and our objectives for future operations, are forward-looking statements. The words “believe,” “may,” “will,” “estimate,” “continue,” “anticipate,” “intend,” “expect,” “should,” “could,” “target,” “predict,” “seek” and similar expressions are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of ~~SerEnergy~~operations, business strategy, short- and long-term business operations and objectives, and financial needs. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those described in “Item 1.A Risk Factors” in our Annual Report on Form 10-K for the ~~period~~year ended December 31, 2024. Moreover, we operate in a very competitive and rapidly changing environment and new risks emerge from ~~January~~time 1to time. It is not possible for our management to predict all risks, ~~2021~~nor can we assess the impact of all factors on our business or the extent to ~~August~~which 31any factor, ~~2021~~or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties and assumptions, the forward-looking events and circumstances discussed in this prospectus may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements.

~~(D)~~Some of ~~Derived from~~ the ~~unaudited~~key ~~statement~~factors ofthat ~~operations~~could ofcause ~~FES~~actual ~~for~~results ~~the~~to ~~period~~differ from ~~January~~our 1,expectations ~~2021 to August 31, 2021.~~include:

~~Pro~~● ~~forma~~our ~~Transaction~~ability ~~Accounting~~to ~~Adjustments~~maintain the listing of our shares of common stock and warrants on Nasdaq;

~~(a)~~● ~~Represents~~our ~~pro~~ability ~~forma adjustment~~ to ~~reflect~~raise ~~the~~financing new compensation arrangements with five key executives of the Combined Entity (Chief Executive Officer, Chief Financial Officer, Chief Marketing Officer, Chief Technology Officer, and Chief Operating Officer and General Counsel and Business Development Representative) in ~~connection with~~ the Business Combination based on the Employment Agreements or Term Sheets entered into on the date of the Merger Agreement, resulting in an aggregate $0.2 million increase in the compensation for these executives from their previous compensation for the period from January 1, 2021 to February 4, 2021, the date of the Merger Agreement.future;

~~(b)~~● ~~Reflects~~our ~~the~~success ~~elimination of non-recurring transaction expenses of both AMCI and Advent~~ in ~~the~~retaining ~~aggregate~~or ~~amount~~recruiting ~~of $5.9 million incurred in connection with the Business Combination~~officers, ~~primarily~~key ~~comprised~~employees ofor transaction bonus agreements with Advent’s management team for aggregate cash bonus payments of $5.0 million payable in connection with the Closing, and one-time signing bonuses with Advent’s management team. This cost is not included in the unaudited pro forma condensed combined statement of operations as it is non-recurring.directors;

~~(c)~~● ~~Represents~~factors ~~pro~~relating ~~forma adjustment~~ to ~~eliminate~~our ~~investment~~business, ~~income~~operations ~~related~~and tofinancial ~~the~~performance, ~~investment held in the Trust Account.~~including:

~~(d)~~○ ~~Represents~~our ~~pro~~ability ~~forma adjustments~~ to ~~eliminate~~control ~~intercompany~~the ~~transactions~~costs ~~between~~associated ~~SerEnergy~~with ~~and~~our ~~FES.~~operations;

~~(e)~~○ ~~Represents~~our ~~incremental~~ability ~~amortization~~to ~~expense~~grow ofand ~~$1.6~~manage ~~million~~growth ~~recorded as a result of the intangible assets recognized in the acquisitions of SerEnergy and FES.~~profitably;

~~(f)~~○ ~~Represents~~our ~~interest~~reliance ~~expense incurred by SerEnergy and FES~~ on ~~loans~~complex ~~from~~machinery ~~the~~for ~~former~~our ~~parent~~operations ~~company, which were acquired by Advent in the acquisition~~ and ~~therefore eliminated from the pro forma results.~~production;

~~(g)~~○ ~~Represents income from loss absorption for FES of $9.0 million, reflecting a profit and loss transfer agreement between FES and its former parent company which was terminated upon~~ the ~~acquisition.~~market’s ~~Due~~willingness to ~~the~~adopt ~~termination~~our ~~of the agreement and the fact that the loss absorption would not be an income statement line item under U.S. GAAP, the loss absorption was eliminated from the pro forma results.~~technology;

~~Note~~○ 5.our ~~Net~~ability ~~Income~~to ~~(Loss)~~maintain ~~per~~relationships ~~Share~~with customers;

~~Represents~~○ the net income (loss) per share calculated using the historical weighted average shares outstanding, and the issuance of additional shares in connection with the Transactions, assuming the shares were outstanding since January 1, 2021. As the Transactions are being reflected as if they had occurred at the beginning of the periods presented, the calculation of weighted average shares outstanding for basic and diluted net loss per share assumes that the shares issuable relating to the Transactions have been outstanding for the entire period presented. As the Company incurred losses for the year ended December 31, 2021, the effect of including any potential ~~common~~impact ~~shares in the denominator~~ of ~~diluted~~product ~~per-share computations would have been anti-dilutive~~recalls; ~~therefore, basic and diluted losses per share are the same.~~

In○ ~~connection~~our ~~with~~ability the merger and PIPE investment, for purposes of applying the if converted method for calculating diluted earnings per share, it was assumed that all outstanding warrants sold in the initial public offering and private placement are converted to ~~Class A~~compete ~~common~~within ~~stock~~our ~~of AMCI. However, since this results in anti-dilution, the effect of such exchange was not included in calculation of diluted loss per share.~~industry;

○

increases in costs, disruption of supply or shortage of raw materials;

○

the impact of unfavorable changes in U.S. and international regulations;

○

the availability of and our ability to meet the terms and conditions for government grants and economic incentives; and

○

our ability to protect our intellectual property rights.

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the regulatory environment in which our business operates under;

●

trends in the industries in which our business operates;

●

the competitive environment in which our business operates;

●

changes in general economic or business conditions or economic or demographic trends in the United States, and globally, including changes in interest rates and inflation;

●

casualties, condemnation or catastrophic failures with respect to any of our business’ facilities;

●

costs and effects of legal and administrative proceedings, settlements, investigations and claims;

●

extraordinary or force majeure events affecting the business or operations of our businesses; and

●

other factors detailed herein under the section entitled “Risk Factors.”

The forward-looking statements included in this prospectus are made only as of the date of this prospectus. You should not rely upon forward-looking statements as predictions of future events. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance or events and circumstances reflected in the forward-looking statements will be achieved or occur. Moreover, neither we nor any other person assumes responsibility for the accuracy and completeness of the forward-looking statements. We undertake no obligation to update publicly any forward-looking statements for any reason after the date of this prospectus to conform these statements to actual results or to changes in our expectations.

As a result of a number of known and unknown risks and uncertainties, our actual results or performance may be materially different from those expressed or implied by these forward-looking statements. For a discussion of the risks involved in our business and investing in our common stock, see the section entitled “Risk Factors.”

Should one or more of these risks or uncertainties materialize, or should any of the underlying assumptions prove incorrect, actual results may vary in material respects from those expressed or implied by these forward-looking statements. You should not place undue reliance on these forward-looking statements.

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HUDSON GLOBAL TRANSACTION

On August 14, 2025, we entered into the Purchase Agreement and the Registration Rights Agreement with Hudson Global. Pursuant to the Purchase Agreement, we have the right to sell to Hudson Global up to $52 million of our common stock (“the “Purchase Shares”)subject to certain limitations and conditions set forth in the Purchase Agreement, from time to time during the term of the Purchase Agreement. Sales of common stock pursuant to the Purchase Agreement, and the timing of any sales, are solely at our option, and we are under no obligation to sell any securities to Hudson Global under the Purchase Agreement. In accordance with our obligations under the Registration Rights Agreement, we have filed the registration statement that includes this prospectus with the SEC to register under the Securities Act the resale by Hudson Global of up to 987,036 shares of common stock that we may elect, in our sole discretion, to issue and sell to Hudson Global, from time to time from and after the execution date of the Purchase Agreement and until the earlier of (i) August 14, 2027, (ii) the date on which the Hudson Global shall have purchased the Total Commitment, or (iii) the effective date of any written notice of termination delivered pursuant to the terms of the Purchase Agreement (the “Commitment Period”).

Purchase of Shares of Common Stock under the Purchase Agreement

We do not have the right to commence any sales of our common stock to Hudson Global under the Purchase Agreement until the Commencement Date, which is the date on which all of the conditions to Hudson Global’s purchase obligation set forth in the Purchase Agreement have been satisfied, including that the registration statement that includes this prospectus be declared effective by the SEC. From and after the Commencement Date, we will have the right, but not the obligation, from time to time at our sole discretion over the 24-month period commencing on the Commencement Date, to direct Hudson Global to make purchases of Purchase Shares, as further described in the Purchase Agreement (each, a “Purchase”) by delivering a Put Notice (as such term is defined in the Purchase Agreement) on any trading day (the trading day during the Commitment Period that a Put Notice is deemed delivered is the “Put Date”). We may not deliver any Put Notice to Hudson Global unless at least three trading days has elapsed since the date on which the most recent prior notice for a Purchase was delivered by us to Hudson Global and all Purchase Shares subject to prior Put Notices have been received by Hudson Global.

The purchase price of the Purchase Shares that we elect to sell to Hudson Global pursuant to a Purchase (the “Purchase Price”) will be the lesser of (i) 84% of the closing price of the Company’s Common Stock, as listed on Nasdaq, on the trading day immediately preceding the respective Put Date (the “Initial Purchase Price”), or (ii) 84% of the lowest closing price of the Company’s Common Stock on the Principal Market on any Trading Day during the period beginning on the Put Date and continuing through the date that is three trading days immediately following the Clearing Date associated with the applicable Put Notice (such three trading day period is the “Valuation Period”, and the price is the “Market Price”), on such date on which the Purchase Price is calculated in accordance with the terms of the Purchase Agreement. The Purchase Price per share of Purchase Shares to be sold in a Purchase will be equitably adjusted for any reorganization, recapitalization, non-cash dividend, stock split, reverse stock split or other similar transaction occurring during the applicable Valuation Period used to compute the purchase price per share for such purchase.

The Company may direct Hudson Global, by its delivery of a Put Notice, to purchase Purchase Shares: (a) in a minimum amount not less than $25,000 (calculated using the Initial Purchase Price); and (b) in a maximum amount up to the lesser of (i) $3,000,000 (calculated using the Initial Purchase Price), and (ii) 200% of the average trading volume of the Company’s Common Stock on the Principal Market during the three Trading Days immediately preceding the respective Put Date, multiplied by the lowest closing price of the Company’s Common Stock on the Principal Market during the three Trading Days immediately preceding the respective Put Date (subsections (a) and (b) above are collectively, the “Purchase Limit”); provided that Hudson Global may waive the Purchase Limit in connection with any Purchase. There is no upper limit on the price per share that Hudson Global could be obligated to pay for Purchase Shares under the Purchase Agreement.

From and after the Commencement Date, we will control the timing and amount of any sales of common stock to Hudson Global. Actual sales of Purchase Shares to Hudson Global under the Purchase Agreement will depend on a variety of factors to be determined by us from time to time, including, among other things, market conditions, the trading price of our common stock and determinations by us as to the appropriate sources of funding for our business and its operations.

¹	NTD: Section to be updated to reflect terms of purchase agreement.

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Under the applicable Nasdaq rules, in no event may we issue to Hudson Global under the Purchase Agreement more than 534,031 shares of common stock, which number of shares is equal to 19.99% of the shares of the common stock outstanding as of the date of the Purchase Agreement (the “Exchange Cap”), unless we obtain stockholder approval to issue shares of common stock in excess of the Exchange Cap in accordance with applicable Nasdaq rules. Moreover, we may not issue or sell any shares of common stock to Hudson Global under the Purchase Agreement which, when aggregated with all other shares of common stock then beneficially owned by Hudson Global and its affiliates (as calculated pursuant to Section 13(d) of the Exchange Act and Rule 13d-3 promulgated thereunder), would result in Hudson Global beneficially owning shares of common stock in excess of the 4.99% Beneficial Ownership Limitation (as such term defined in the Purchase Agreement).

Conditions to Delivery of Advance Notices

Our ability to deliver Put Notices to Hudson Global under the Purchase Agreement, and Hudson Global’s obligation to accept Put Notices delivered by us, are subject to (i) the initial satisfaction, at the Commencement, and (ii) the satisfaction, on the applicable Put Date for each Purchase after the Commencement Date, of the conditions precedent thereto set forth in the Purchase Agreement, which conditions include the following:

●

the accuracy in all material respects of our representations and warranties included in the Purchase Agreement;

●

the registration statement that includes this prospectus (and any one or more additional registration statements filed with the SEC that include shares of common stock that may be issued and sold by us to Hudson Global under the Purchase Agreement) shall continue to be effective under the Securities Act, and Hudson Global is able to utilize this prospectus to resell all of the shares of common stock included in this prospectus (and included in any such additional prospectuses);

●

the SEC shall not have issued any stop order suspending the effectiveness of the registration statement that includes this prospectus (or any one or more additional registration statements filed with the SEC that include shares of common stock that may be issued and sold by us to Hudson Global under the Purchase Agreement) or prohibiting or suspending the use of this prospectus;

●

Both us and Hudson Global shall have performed, satisfied and complied in all material respects with all covenants, agreements and conditions required by the Purchase Agreement to be performed, satisfied or complied with by such party;

●

trading in our common stock shall not have been suspended by the SEC, Nasdaq, or the Financial Industry Regulatory Authority (“FINRA”), and we shall not have received any final and non-appealable notice that the listing of our common stock on The Nasdaq Capital Market shall be terminated on a date certain (unless, prior to such date, the common stock is listed or quoted on any other Eligible Market, as such term is defined in the Purchase Agreement); and

●

there shall be the absence of any action, suit or proceeding before any arbitrator or any court or governmental authority seeking to restrain, prevent or change the transactions contemplated by the Purchase Agreement, or seeking material damages in connection with such transactions.

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Termination of Purchase Agreement

Unless earlier terminated as provided in the Purchase Agreement, the Purchase Agreement will terminate automatically on the earliest to occur of:

●

twenty-four (24) months after the execution of the Purchase Agreement;

●

the date on which the Hudson Global shall have purchased the Maximum Commitment Amount issuable under the Purchase Agreement; or

●

the effective date of any written notice of termination delivered pursuant to the terms of the Purchase Agreement.

We have the right to terminate the Purchase Agreement at any time after the Commencement Date for any reason or for no reason, without any liability whatsoever, upon prior written notice to Hudson Global, provided that Hudson Global no longer holds any Purchase Shares and such notice is not delivered during a Valuation Period.

Prohibitions on Other Equity Lines of Credit

Pursuant to the terms of the Purchase Agreement, during the period beginning on the date of the Purchase Agreement and continuing until the later of (i) 12 months from the date of the Purchase Agreement or (ii) the date that the Purchase Agreement is no longer in effect, the Company has agreed that it will not, without Hudson’s prior written consent, enter into any other “Equity Line of Credit,” and that, for so long as the Purchase Agreement is in effect, the Company will not enter into any “Variable Rate Transaction” without Hudson’s prior written consent.

“Equity Line of Credit” is defined as any transaction involving a written agreement between the Company and an investor or underwriter whereby the Company has the right to “put” its securities to the investor or underwriter over an agreed period of time and at an agreed price or price formula.

“Variable Rate Transaction” is defined as a transaction in which the Company (i) issues or sells any debt or equity securities that are convertible into, exchangeable or exercisable for, or include the right to receive, additional shares of Common Stock either (A) at a conversion price, exercise price or exchange rate or other price that is based upon, and/or varies with, the trading prices of or quotations for the shares of Common Stock at any time after the initial issuance of such debt or equity securities or (B) with a conversion, exercise or exchange price that is subject to being reset at some future date after the initial issuance of such debt or equity security or upon the occurrence of specified or contingent events directly or indirectly related to the business of the Company or the market for the Common Stock or (ii) issues securities at a future determined price, provided, however, that an Equity Line of Credit shall not be deemed to be a Variable Rate Transaction.

Effect of Sales of our Common Stock under the Purchase Agreement on our Stockholders

All shares of common stock that may be issued or sold by us to Hudson Global under the Purchase Agreement that are being registered under the Securities Act for resale by Hudson Global in this offering are expected to be freely tradable. The shares of common stock being registered for resale in this offering may be issued and sold by us to Hudson Global from time to time at our discretion over a period of up to 24 months commencing on the Commencement Date. The resale by Hudson Global of a significant amount of shares registered for resale in this offering at any given time, or the perception that these sales may occur, could cause the market price of our common stock to decline and to be highly volatile. Sales of our common stock, if any, to Hudson Global under the Purchase Agreement will depend upon market conditions and other factors to be determined by us. We may ultimately decide to sell to Hudson Global all, some or none of the shares of our common stock that may be available for us to sell to Hudson Global pursuant to the Purchase Agreement.

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If and when we do elect to sell shares of our common stock to Hudson Global pursuant to the Purchase Agreement, after Hudson Global has acquired such shares, Hudson Global may resell all, some or none of such shares at any time or from time to time in its discretion and at different prices. Therefore, sales to Hudson Global by us under the Purchase Agreement may result in substantial dilution to the interests of other holders of our common stock. In addition, if we sell a substantial number of shares to Hudson Global under the Purchase Agreement, or if investors expect that we will do so, the actual sales of shares or the mere existence of our arrangement with Hudson Global may make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise wish to effect such sales. However, we have the right to control the timing and amount of any additional sales of our shares to Hudson Global and the Purchase Agreement may be terminated by us at any time at our discretion without any cost to us.

Pursuant to the terms of the Purchase Agreement, we have the right, but not the obligation, to direct Hudson Global to purchase up to $52,000,000 of our common stock. The Purchase Agreement prohibits us from issuing or selling to Hudson Global under the Purchase Agreement shares of our common stock in excess of the Exchange Cap, unless we obtain stockholder approval to issue shares in excess of the Exchange Cap and any shares of our common stock if those shares, when aggregated with all other shares of our common stock then beneficially owned by Hudson Global, would exceed the 4.99% of our outstanding shares of common stock.

The following table sets forth the sale of shares of common stock to Hudson Global under the Purchase Agreement at varying purchase prices:

Assumed Average Purchase Price			Number of Registered Shares to be Issued if Full Purchase⁽¹⁾		Percentage of Outstanding Shares After Giving Effect to the Issuance to Hudson Global⁽²⁾
$	3.00			17,333,333		86.65	%
$	3.68	⁽³⁾		14,130,435		84.11	%
$	4.00			13,000,000		82.96	%
$	4.50			11,555,556		81.23	%
$	5.00			10,400,000		79.57	%

	(1)	Includes the total number of Purchase Shares that we would have sold under the Purchase Agreement at the corresponding assumed average purchase price set forth in the first column, up to the aggregate purchase price of $52,000,000, if available, without giving effect to the Exchange Cap or the Beneficial Ownership Cap. Also assumes an increase of our authorized shares of common stock when the assumed average purchase price equals to $3.00, $3.68, $4.00, $4.50 or $5.00. The assumed average purchase prices per share are solely for illustrative purposes and are not intended to be estimates or predictions of the future performance of our common stock. Also assumes stockholder approval for the potential issuance and sale of 20% or more of our common stock to Hudson Global pursuant to the Purchase Agreement.
	(2)	The denominator is based on 2,670,286 shares of our common stock outstanding as of August 14, 2025, as adjusted to include the sale of the number of shares set forth in the adjacent column (which is comprised of the number of shares we may sell to Hudson Global under the Purchase Agreement, assuming the average purchase price in the first column). The numerator is based on the aggregate number of shares issuable under the Purchase Agreement (that are the subject of this offering) at the corresponding assumed average purchase price set forth in the first column.
	(3)	The closing sale price of our common stock on The Nasdaq Capital Market on August 14, 2025.

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USE OF PROCEEDS

This prospectus relates to shares of our common stock that may be offered and sold from time to time by Hudson Global. All of the common stock offered by Hudson Global pursuant to this prospectus will be sold by Hudson Global for its own account. We will not receive any of the proceeds from these sales. We may receive up to $52 million aggregate gross proceeds under the Purchase Agreement from any sales we make to Hudson Global pursuant to the Purchase Agreement. The net proceeds from sales, if any, under the Purchase Agreement, will depend on the frequency and prices at which we sell shares of common stock to Hudson Global after the date of this prospectus. Because we are not obligated to sell any shares of our common stock under the Purchase Agreement, the actual total offering amount and proceeds to us, if any, are not determinable at this time. See the section titled “Plan of Distribution” elsewhere in this prospectus for more information.

We expect to use the net proceeds that we receive from sales of our common stock to the Hudson Global, if any, under the Purchase Agreement to fund the operating expenses and capital expenses for product development and plan to make substantial investments over the next several years, among others, in new production equipment and warehousing, systems assembly line, MEA assembly automation, aeronautical stacks, facility expansion, new hirings and general corporate purposes., including, but not limited to, for use with respect to certain projects of the Company’s subsidiary, Advanced Energy Technologies S.A. We do not currently have specific plans or commitments with respect to the net proceeds from this offering and, accordingly, we are unable to quantify the allocations of such proceeds among various potential uses. Pending these uses, we intend to invest the net proceeds in investment-grade, interest-bearing securities. There can be no assurance that we will sell any shares under or fully utilize the Purchase Agreement as a source of financing.

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SELLING STOCKHOLDER

This prospectus relates to the offer and resale by Hudson Global of up to 987,036 shares of common stock that have been and may be issued by us to Hudson Global under the Purchase Agreement. For additional information regarding the shares of common stock included in this prospectus, see the section titled “Hudson Global Transaction” above. We are registering the shares of common stock included in this prospectus pursuant to the provisions of the Registration Rights Agreement we entered into with Hudson Global on August 14, 2025 in order to permit Hudson Global to offer the shares included in this prospectus for resale from time to time.

The table below presents information regarding Hudson Global and the shares of common stock that may be resold by Hudson Global from time to time under this prospectus. This table is prepared based on information supplied to us by Hudson Global, and reflects holdings as of August 14, 2025. The number of shares in the column “Maximum Number of Shares of Common Stock to be Offered Pursuant to this Prospectus” represents all of the shares of common stock being offered for resale by Hudson Global under this prospectus. Hudson Global may sell some, all or none of the shares being offered for resale in this offering. We do not know how long Hudson Global will hold the shares before selling them, and we are not aware of any existing arrangements between Hudson Global and any other stockholder, broker, dealer, underwriter or agent relating to the sale or distribution of the shares of our common stock being offered for resale by this prospectus.

Beneficial ownership is determined in accordance with Rule 13d-3(d) promulgated by the SEC under the Exchange Act, and includes shares of common stock with respect to which Hudson Global has sole or shared voting and investment power. The percentage of shares of common stock beneficially owned by Hudson Global prior to the offering shown in the table below is based on an aggregate of 2,670,286 shares of our common stock outstanding on August 14, 2025. Because the purchase price to be paid by Hudson Global for shares of common stock, if any, that we may elect to sell to Hudson Global from time to time under the Purchase Agreement will be determined on the applicable dates for such purchases, the actual number of shares of common stock that we may sell to Hudson Global under the Purchase Agreement may be fewer than the number of shares being offered for resale under this prospectus. The fourth column assumes the resale by Hudson Global of all of the shares of common stock being offered for resale pursuant to this prospectus.

	Selling Stockholders
Selling Stockholder⁽¹⁾	Shares of Common Stock Beneficially Owned Prior to Offering⁽²⁾		%⁽³⁾	Maximum Number of Shares of Common Stock to be Offered Pursuant to this Prospectus		Shares of Common Stock Beneficially Owned after the Offered Shares are Sold⁽⁴⁾		%
Hudson Global Ventures, LLC		0			987,036		987,036		36.96

(1)	Seth Ahdoot and Soheil Ahdoot, the joint owners of Hudson Global], are deemed to be beneficial owners of all of the shares of common stock owned by Hudson Global. Messrs. Ahdoot and Ahdoot have shared voting and investment power over the shares being offered under the prospectus in connection with the transactions contemplated under the Purchase Agreement. Hudson Global is not a licensed broker dealer or an affiliate of a licensed broker dealer.
(2)	In accordance with Rule 13d-3(d) under the Exchange Act, we have excluded from the number of shares beneficially owned prior to the offering of all of the shares that Hudson Global may be required to purchase under the Purchase Agreement, because the issuance of such shares is solely at our discretion and is subject to conditions contained in the Purchase Agreement, the satisfaction of which are entirely outside of Hudson Global’s control, including the registration statement that includes this prospectus becoming and remaining effective. Also, the Purchase Agreement prohibits us from issuing and selling any shares of our common stock to Hudson Global to the extent such shares, when aggregated with all other shares of our common stock then beneficially owned by Hudson Global, would cause Hudson Global’s beneficial ownership of our common stock to exceed the 4.99% Beneficial Ownership Limitation. The Purchase Agreement also prohibits us from issuing or selling shares of our common stock under the Purchase Agreement in excess of the 19.99% Exchange Cap, unless we obtain stockholder approval to do so. Neither the Beneficial Ownership Limitation nor the Exchange Cap (to the extent applicable under Nasdaq rules) may be amended or waived under the Purchase Agreement.
(3)	Applicable percentage ownership is based on 2,670,286 shares of our common stock outstanding as of August 14, 2025.
(4)	Assumes the resale of all shares being offered pursuant to this prospectus.

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PLAN OF DISTRIBUTION

The shares of common stock offered by this prospectus are being offered by the Selling Stockholder, Hudson Global. The shares may be sold or distributed from time to time by Hudson Global directly to one or more purchasers or through brokers, dealers, or underwriters who may act solely as agents at market prices prevailing at the time of sale, at prices related to the prevailing market prices, at negotiated prices, or at fixed prices, which may be changed.

We entered into the Purchase Agreement with Hudson Global on August 14, 2025. The Purchase Agreement provides that, upon the terms and subject to the conditions set forth therein, Hudson Global is committed to purchase an aggregate of up to $52,000,000 of our common stock over the 24-month term of the Purchase Agreement. See section titled “Hudson Global Transaction.”

The sale of the shares of our common stock offered by this prospectus could be effected in one or more of the following methods:

●

ordinary brokers’ transactions;

●

transactions involving cross or block trades;

●

through brokers, dealers or underwriters who may act solely as agents;

●

“at the market” into an existing market for our common stock;

●

in other ways not involving market makes or established business markets, including direct sales to purchasers or sales effected through agents;

●

in privately negotiated transactions;

●

any combination of the foregoing; or.

●

any other method permitted pursuant to applicable law.

In order to comply with the securities laws of certain states, if applicable, the shares may be sold only through registered or licensed brokers or dealers.

Hudson Global is an “underwriter” within the meaning of Section 2(a)(11) of the Securities Act.

Hudson Global has informed us that it intends to use an unaffiliated broker to effectuate all sales, if any, of our common stock that it may acquire from us pursuant to the Purchase Agreement. Such sales will be made at prices and at terms then prevailing or at prices related to the then current market price. Each such registered broker-dealer will be an underwriter within the meaning of Section 2(a)(11) of the Securities Act. Hudson Global has informed us that each such broker-dealer, may receive commissions from Hudson Global for executing such sales for Hudson Global and, if so, such commissions will not exceed customary brokerage commissions.

Brokers, dealers, underwriters or agents participating in the distribution of the shares of our common stock offered by this prospectus may receive compensation in the form of commissions, discounts, or concessions from the purchasers, for whom the broker-dealers may act as agent, of the shares sold by Hudson Global through this prospectus. The compensation paid to any such particular broker-dealer by any such purchasers of shares of our common stock sold by Hudson Global may be less than or in excess of customary commissions. Neither we nor Hudson Global can presently estimate the amount of compensation that any agent will receive from any purchasers of shares of our common stock sold by Hudson Global.

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We know of no existing arrangements between Hudson Global and any other stockholder, broker, dealer, underwriter, or agent relating to the sale or distribution of the shares offered by this prospectus.

We may from time to time file with the SEC one or more supplements to this prospectus or amendments to the registration statement of which this prospectus forms a part to amend, supplement or update information contained in this prospectus, including, if and when required under the Securities Act, to disclose certain information relating to a particular sale of shares offered by this prospectus by Hudson Global, including with respect to any compensation paid or payable by Hudson Global to any brokers, dealers, underwriters or agents that participate in the distribution of such shares by Hudson Global, and any other related information required to be disclosed under the Securities Act. At the time a particular offer of shares is made, a prospectus supplement, if required, will be distributed that will set forth the names of any agents, underwriters, or dealers and any compensation from the selling stockholder, and any other required information.

We may engage in “at-the-market offerings” into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

We will pay all of the expenses incident to the registration, offering, and sale of the shares to Hudson Global.

We have agreed to indemnify Hudson Global and certain other persons against certain liabilities in connection with the offering of shares of common stock offered hereby, including liabilities arising under the Securities Act or, if such indemnity is unavailable, to contribute amounts required to be paid in respect of such liabilities.

Hudson Global represented to us that at no time prior to the date of the Purchase Agreement has Hudson Global or its agents, representatives or affiliates engaged in or effected, in any manner whatsoever, directly or indirectly, any short sale (as such term is defined in Rule 200 of Regulation SHO of the Exchange Act) of our common stock or any hedging transaction. Hudson Global agreed that during the term of the Purchase Agreement, it, its agents, representatives or affiliates will not enter into or effect, directly or indirectly, any of the foregoing transactions.

We have advised Hudson Global that it is required to comply with Regulation M promulgated under the Exchange Act. With certain exceptions, Regulation M precludes Hudson Global, any affiliated purchasers, and any broker-dealer or other person who participates in the distribution from bidding for or purchasing, or attempting to induce any person to bid for or purchase any security which is the subject of the distribution until the entire distribution is complete. Regulation M also prohibits any bids or purchases made in order to stabilize the price of a security in connection with the distribution of that security. All of the foregoing may affect the marketability of the shares offered by this prospectus.

The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

No securities may be sold under this prospectus without delivery, in paper format or in electronic format, or both, of the applicable prospectus or prospectus supplement describing the method and terms of the offering.

Listing of Common Stock and Transfer Agent

Our common stock is listed on Nasdaq and trades under the symbol “ADN.” The transfer agent for our common stock is Continental Stock Transfer & Trust Company.

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DIVIDEND POLICY

We have not declared any cash dividends since inception and we do not anticipate paying any dividends in the foreseeable future. Instead, we anticipate that all of our earnings will be used to provide working capital, to support our operations, and to finance the growth and development of our business, including potentially the acquisition of, or investment in, businesses, technologies or products that complement our existing business. The payment of dividends is within the discretion of the board of directors and will depend on our earnings, capital requirements, financial condition, prospects, applicable Delaware law, which provides that dividends are only payable out of surplus or current net profits, and other factors our board might deem relevant. There are no restrictions that currently limit our ability to pay dividends on our common stock other than those generally imposed by applicable state law.

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CAPITALIZATION

The following table sets forth our capitalization as of August 14, 2025:

●

on an actual basis;

●

on an as adjusted basis, giving effect to the assumed sale by us of 987,036 shares of Common Stock in this offering at an assumed public offering price of $3.68 per share (the last reported sale price of our Common Stock on Nasdaq on August 14, 2025), after estimated offering expenses payable by us.

The as adjusted information below is illustrative only and our capitalization following the completion of this offering is subject to adjustment based on the public offering price and other terms of this offering determined at pricing. You should read this table together with our financial statements and the related notes included elsewhere in this prospectus and the information under “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

	Actual			As adjusted
Cash, cash equivalents and investments	$	30			3,662

Common stock, $0.0001 par value; 501,000,000 shares authorized at August 14, 2025; 2,670,286 shares issued and outstanding at August 14, 2025; 3,657,322 shares issued and outstanding, as adjusted	$	-			-
Additional paid-in capital	$	199,565			203,197
Accumulated deficit	$	(215,443	)		(215,443	)
Accumulated other comprehensive loss	$	(1,763	)		(1,763	)
Total stockholders’ equity	$	(17,641	)		(14,009	)
Total capitalization	$	(17,641	)		(14,009	)

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DILUTION

If you invest in our securities in this offering, your ownership will be diluted immediately to the extent of the difference between the public offering price per share and the as adjusted net tangible book value per Common Stock of immediately after this offering. Dilution in net tangible book value per share to new investors is the amount by which the offering price paid by the purchasers of the shares sold in this offering exceeds the pro forma as adjusted net tangible book value per Common Stock after this offering. Net tangible book value per share is determined at any date by subtracting our total liabilities from the total book value of our tangible assets and dividing the difference by the number of Common Stock deemed to be outstanding at that date.

As of August 14, 2025, our net tangible book value (deficit) was approximately $(17,641), or approximately $(6.61) per share.

After giving effect to the sale of the maximum of 987,036 Common Stock in this offering, and after deducting the placement agent fees and other estimated offering expenses payable by us, our pro forma as adjusted net tangible book value (deficit) as of August 14, 2025 would have been approximately $(14,024), or approximately $(3.83) per share. This amount represents an immediate increase in net tangible book value of $2.77 per share to existing shareholders and an immediate dilution in net tangible book value of $7.51 per share to purchasers of our Common Stock in this offering, as illustrated in the following table.

Assumed public offering price per share				$	3.68
Historical net tangible book value (deficit) per share as of August 14, 2025	$	(6.61	)
Increase per share attributable to the pro forma adjustments described above		2.77
Pro forma net tangible book value (deficit) per share as of August 14, 2025		(3.83	)
Increase in pro forma as adjusted net tangible book value per share attributable to new investors purchasing shares in this offering		3.68
Pro forma as adjusted net tangible book value (deficit) per share after this offering					(3.83	)
Dilution per share to new investors purchasing shares in this offering				$	7.51

The table and discussion above exclude:

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MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL
CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis ~~should~~of ~~be read~~our ~~in conjunction with the~~ financial ~~statements~~condition and related notes included elsewhere in this prospectus. This discussion contains “forward-looking statements” reflecting Advent’s current expectations, estimates and assumptions concerning events and financial trends may affect its future operating results ~~or financial position. Actual results and the timing~~ of ~~events~~operations ~~may~~should ~~differ~~be ~~materially~~read ~~from those contained~~ in ~~these~~conjunction ~~forward-looking~~with ~~statements~~our ~~due to a number of factors. Factors that~~consolidated ~~could~~financial ~~cause~~statements ~~or contribute to such differences include, but are not limited to, economic~~ and ~~competitive~~related ~~conditions,~~notes ~~regulatory~~appearing ~~changes~~elsewhere ~~and other uncertainties, as well as those factors included~~ in this prospectus~~, all of which are difficult to predict~~. In light of these risks, uncertainties and assumptions, the forward-looking events discussed may not occur. Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. There may be additional risks that we consider immaterial or which are unknown. It is not possible to predict or identify all such risks. We do not undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

Some of the information contained in this discussion and analysis or set forth elsewhere in this prospectus, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the Item 1A. “Risk Factors” section of the 2024 10-K, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis.

This MD&A generally discusses 2024 and 2023 items, year-over-year comparisons between 2024 and 2023 and items from the second quarter of 2025. See Note 1 “Basis of Presentation” in the Notes to the Consolidated Financial Statements included with the 2024 10-K beginning on page F-44 and the Notes to Condensed Consolidated Financial Statements (Unaudited) beginning on page F-11 for additional information.

Overview

Advent is an advanced materials and technology development company operating in the fuel cell and hydrogen technology space. Advent develops, manufactures and assembles the critical components that determine the performance of hydrogen fuel cells and other energy systems. Advent’s core product offerings are full fuel cell systems and the Membrane Electrode Assembly (MEA) at the center of the fuel cell. The Advent MEA, which derives its key benefits from the properties of Advent’s engineered membrane technology, enables a more robust, longer-lasting and ultimately lower-cost fuel cell product.

~~To date,~~ Advent’s principal operations have been to develop and manufacture MEAs, and to design fuel cell stacks and complete fuel cell systems for a range of customers in the stationary power, portable power, automotive, aviation, energy storage and sensor markets. Advent has its headquarters ~~in Boston,~~ ~~Massachusetts, a product development facility~~ in Livermore, California, and ~~production~~we ~~facilities~~have inMEA ~~Greece,~~fabrication ~~Denmark,~~and ~~Germany~~system ~~and~~production ~~Philippines.~~facilities Inin ~~2022~~Livermore, ~~Advent~~California ~~anticipates opening its new research~~ and ~~development and manufacturing facility at Hood Park in Charlestown~~Patras, ~~Massachusetts~~Greece.

The majority of Advent’s current revenue derives from the sale and servicing of fuel cell systems and MEAs, as well as the sale of membranes and electrodes for specific applications in the iron flow battery and cellphone markets, respectively. While fuel cell systems and MEA sales and associated revenues are expected to provide the majority of Advent’s future income, both of these markets remain commercially viable and have the potential to generate material future revenues based on Advent’s existing customers. Advent has also secured grant funding for a range of projects from research agencies and other organizations. Advent expects to continue to be eligible for grant funding based on its product development activities over the foreseeable future.

Business Combination and Public Company Costs

On October 12, 2020, Advent Technologies Inc. (“Advent Technologies”) entered into the Merger Agreement with Advent Technologies Holdings, Inc. (formerly known as “AMCI”), a Delaware corporation, AMCI Merger Sub Corp., a newly-formed Delaware corporation and wholly-owned subsidiary of AMCI (“Merger Sub”), AMCI Sponsor LLC, a Delaware limited liability company (“Sponsor”), in its capacity as Purchaser Representative (the “Purchaser Representative”) and Vassilios Gregoriou, in the capacity as Seller Representative ( the “Seller Representative”), pursuant to which, effective February 4, 2021 (the “Closing”), Merger Sub merged with and into Advent Technologies Inc., with Advent Technologies Inc. surviving the Merger as a wholly-owned subsidiary of AMCI and AMCI changed its name to “Advent Technologies Holdings, Inc.”. Advent Technologies Inc. is deemed the accounting predecessor and the combined entity is the successor registrant with the SEC, meaning that Advent Technologies Inc.’s financial statements for previous periods are and will be disclosed in the company’s current and future periodic reports filed with the SEC.

While the legal acquirer in the Merger Agreement is AMCI, for financial accounting and reporting purposes under GAAP, we have determined that Advent Technologies is the accounting acquirer and the Business Combination will be accounted for as a “reverse recapitalization.” A reverse recapitalization does not result in a new basis of accounting, and the financial statements of the combined entity represent the continuation of the financial statements

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of Advent Technologies in many respects. Under this method of accounting, AMCI is treated as the acquired entity whereby Advent Technologies is deemed to have issued common stock for the net assets and equity of AMCI, consisting mainly of cash, accompanied by a simultaneous equity recapitalization of AMCI (the “Recapitalization”).

Upon consummation of the Business Combination, the most significant change in Advent Technologies’s reported financial position and results was an increase in cash of approximately $141 million. Total direct and incremental transaction costs of AMCI and Advent Technologies, along with liabilities of AMCI paid off at the Closing, were approximately $23.6 million.

As a consequence of the Business Combination, Advent Technologies became the successor to an SEC -registered and Nasdaq-listed company which has required and will require Advent to hire additional personnel and implement procedures and processes to address public company regulatory requirements and customary practices. Advent expects to incur additional annual expenses as a public company for, among other things, directors’ and officers’ liability insurance, director fees and additional internal and external accounting, legal and administrative resources, including increased audit and legal fees.

Additionally, Advent anticipates that its revenue, capital and operating expenditures will increase significantly in connection with its ongoing activities following the Business Combination, as Advent expects to:

• Expand U.S.-based operations to increase capacity for product testing, development projects and associated research and development activities;

• Expand production facilities to increase and automate assembly and production of fuel cell systems and MEAs;

• Develop improved MEA and other products for both existing and new markets, such as ultra-light MEAs designed for aviation applications, to remain at the forefront of the fast-developing hydrogen economy;

• Increase business development and marketing activities;

• Increase headcount in management and head office functions in order to appropriately manage Advent’s increased operations;

• Improve its operational, financial and management information systems;

• Obtain, maintain, expand, and protect its intellectual property portfolio; and

• Operate as a public company.

Change in Independent Registered Public Accounting Firm

On ~~February~~ September 917, ~~2021~~2024, ~~the audit committee of the board of directors of the Company approved the engagement of~~ Ernst & Young (Hellas) Certified Auditors Accountants S.A. (“EY”), as the Company’s prior independent registered public accounting firm, towas ~~audit~~dismissed ~~the~~effective ~~Company’s consolidated financial statements for the year ending December 31, 2021~~immediately. EY had served as ~~independent registered public accounting firm of Advent prior to~~ the ~~Business Combination. Accordingly, Marcum LLP (“Marcum”), the~~ Company’s independent registered public ~~accounting~~account firm ~~prior~~since toFebruary 9, ~~the Business Combination~~2021, ~~was~~and ~~informed~~also ~~that~~served ~~it would be replaced by EY~~ as the ~~Company’s~~ independent registered public accounting firm ~~following completion~~ of ~~its audit of~~ the Company’s ~~financial~~subsidiary, ~~statements~~Legacy ~~for the fiscal year ended December 31~~Advent, ~~2020, which~~prior ~~consists~~to ~~only~~the ofBusiness ~~the~~Combination ~~accounts~~pursuant ofto the ~~pre-Business~~Agreement ~~Combination~~and ~~special~~Plan ~~purpose~~of ~~acquisition company~~Merger.

On September 20, 2024, the audit committee of the board of directors of the Company approved the engagement of M&K CPAS, PLLC (“M&K”) as the Company’s independent registered public accounting firm to audit the Company’s consolidated financial statements for the year ending December 31, 2024.

EY’s audit reports on the Company’s financial statements as of and for the fiscal years ended December 31, 2023 and 2022 did not contain an adverse opinion or a disclaimer of opinion and were not qualified or modified as to uncertainty, audit scope or accounting principles, provided that EY’s audit report as of and for the year ended December 31, 2023 contained an explanatory paragraph regarding the Company’s ability to continue as a going concern.

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Reverse Stock Split

On May 13, 2024, the Company effected a 1-for-30 reverse stock split by filing an amendment to the Company’s Second Amended and Restated Certificate of Incorporation, with the Delaware Secretary of State. The reverse stock split combined every thirty shares of our common stock issued and outstanding immediately prior to effecting the reverse stock split into one share of common stock. No fractional shares were issued in connection with the reverse stock split. All historical share and per share amounts reflected throughout this document have been adjusted to reflect the reverse stock split. The authorized number of shares and the par value per share of the Company’s common stock were not affected by the reverse stock split.

Danish Subsidiary Bankruptcy

Additionally, on July 25, 2024, Advent Technologies A/S, a Danish subsidiary of the Company (the “Danish Subsidiary”), was declared bankrupt under and pursuant to the Denmark Bankruptcy Act (the “Danish Subsidiary Bankruptcy”), and, as a result, Advent Technologies A/S and its wholly-owned Philippines subsidiary, Green Energy Philippines Inc., was deconsolidated from the Company.

Business Developments

~~Share~~RHyno Project ~~Purchase~~awarded ~~Agreement~~€34.5 Million by EU Innovation Fund

On ~~August~~ March 315, ~~2021~~2025, ~~pursuant to~~ the ~~Share~~European ~~Purchase Agreement (the “Purchase Agreement”)~~Climate, ~~dated~~Infrastructure ~~as of June 25, 2021, by~~ and ~~between~~Environment ~~Advent~~Executive ~~Technologies~~Agency ~~Holdings, Inc.~~ (~~the “Company” or the “Buyer”~~CINEA) and ~~F.E.R.~~Advent’s ~~fischer~~wholly ~~Edelstahlrohre~~owned ~~GmbH~~Greek subsidiary, aAdvanced ~~limited~~Energy ~~liability~~Technologies ~~company~~S.A. ~~incorporated~~each ~~under~~signed the ~~Laws~~grant ofagreement ~~Germany~~for (the ~~“Seller”),~~ ~~the~~ Company’s ~~acquired~~monumental ~~(the~~RHyno ~~“Acquisition”)~~Project. ~~all of the issued and outstanding equity interests in SerEnergy A/S, a Danish stock corporation and a wholly-owned subsidiary of the Seller (“SerEnergy”) and fischer eco solutions GmbH, a German~~This ~~limited~~EU ~~liability~~Innovation ~~company~~Fund ~~and~~grant awill ~~wholly-owned~~provide ~~subsidiary~~Advent ~~of the Seller (“FES” and together~~ with ~~SerEnergy~~€34, ~~the “Target Companies”)~~534,318 ~~together~~in ~~with~~non-dilutive ~~certain~~funding ~~outstanding~~over ~~shareholder loan receivables. As consideration for~~ the ~~transactions~~lifetime ~~contemplated by~~of the ~~Purchase Agreement, the Company paid to the Seller~~ project.

37The Advent Renewable Hydrogen Innovative Technologies (RHyno) project involves the establishment of infrastructure for developing and manufacturing innovative fuel cells, electrolysers, and their key components including Advent ground-breaking Membrane Electrode Assembly technology at a megawatt (MW) scale. RHyno aims to pioneer the use of innovative materials to enhance power density and lifespan while significantly reducing the weight and volume of power systems through a streamlined balance of plant.

~~TABLE~~The planned OFstate-of-the-art ~~CONTENTS~~facility is designed to optimize production processes, boost efficiency, and industrialize fuel cell and electrolyser technologies. These advancements are essential for decarbonizing carbon intense industries, such as the aviation, maritime and heavy-duty automotive sectors, with further potential for spillover to other sectors, positioning Advent at the forefront of the clean energy transition.

~~€15,000,000~~Airbus Term inSheet ~~cash and on August 31, 2021, the Company issued~~ to ~~the~~Launch ~~Seller 5,124,846 shares~~a ofJoint ~~common~~Benchmarking ~~stock, par value $0.0001 per share, of the Company (“Common Stock”).~~ Project

~~Pursuant~~On November 6, to2023, ~~the~~Advent ~~Purchase~~announced ~~Agreement,~~that ~~the~~it ~~Company~~entered ~~acquired~~into ~~SerEnergy and~~an ~~FES,~~agreement ~~the~~with ~~fuel~~Airbus, ~~cell~~a ~~systems~~global ~~business~~leader ofin ~~fischer~~aeronautics, ~~Group.~~space, ~~SerEnergy~~and isrelated services, for a ~~leading~~joint ~~manufacturer~~benchmarking ofproject ~~methanol-powered~~regarding ~~high-temperature~~an ~~polymer~~optimized ~~electrolyte~~Ion ~~membrane~~Pair™ Membrane Electrode Assembly (“~~HT-PEM~~MEA”) for hydrogen fuel cells. ~~and~~Airbus ~~operates~~will ~~facilities~~provide infinancial ~~Aalborg,~~support ~~Denmark~~to ~~and~~the inproject ~~Manila, Philippines. FES provides fuel-cell stack assembly~~ and ~~testing~~its asextensive ~~well~~knowledge asof the ~~production~~aviation ofindustry. ~~critical~~Advent will ~~fuel~~invest ~~cell~~in ~~components~~people, ofmaterials, ~~the~~hardware, ~~SerEnergy~~and HTthird-~~PEM~~party ~~fuel~~research ~~cells~~centers, ~~including~~to ~~membrane~~contribute ~~electrode~~to ~~assemblies,~~the ~~bipolar~~goals ~~plates~~of ~~and~~the ~~reformers~~project. ~~FES~~The ~~operates a~~multi-million-dollar ~~facility~~collaboration onis ~~fischer~~currently ~~Group’s~~expected ~~campus~~to intake ~~Achern,~~place ~~Germany,~~over ~~and~~two ~~Advent~~years. ~~agreed~~On toFebruary 19, ~~lease~~2025, ~~that~~Advent ~~respective~~and ~~portion~~Airbus ofrepresentatives ~~the~~met ~~facility~~in Hamburg, atGermany ~~the~~to ~~closing~~kickoff Phase Two of the ~~Acquisition.~~joint benchmarking project.

~~Announced~~The goal ~~Projects~~of ~~White~~the ~~Dragon~~project &is ~~Green~~to ~~HiPo~~accelerate the development of Advent’s MEA and benchmark the Ion Pair MEA against aviation requirements (4and current/expected technological limits.~~65GW~~ ~~Green~~HT-PEM ~~Hydrogen~~MEAs &operating ~~400MW~~at ~~Fuel~~temperatures ~~Cells~~higher than 180°C (360°F), ~~approved~~aim byto ~~Greek~~solve ~~Government~~one of the largest challenges in aviation fuel cell use: thermal management. High-temperature fuel cells allow increased performance, increased passenger carrying capability, and ~~submitted~~increased range compared to EUlow-temperature fuel cell stack technology. Advent believes that HT-PEM is a superior option not only for aviation, but also for heavy-duty trucks, the automotive industry and marine use.

On September 7, 2021, Advent announced that two Greek Important Projects of Common European Interest (“IPCEI”) had been approved by the Greek Minister of Development and Investments and the Greek Minister of Environment, Energy, and Climate Change. The programs submitted by Advent and the White Dragon consortium of companies aspire to replace Greece’s largest coal-fired plants with renewable solar energy parks, which will be supported by green hydrogen production (4.65GW), and fuel cell heat and power production (400MW). The projects are part of the “Hydrogen Technologies” IPCEI and will now move towards approval at the European Union (“EU”) level. As a next step, Advent will demonstrate before the European Commission the economic, environmental, financial, social, and technical feasibility of the projects and the positive spillover effects to the European economy and society. Advent hopes to receive final notification from the European Commission in the second or third quarter of 2022. If approved, the Company will be the technology partner for an €8 billion project.49

~~Collaboration~~Table ~~with~~of ~~the DOE~~ Contents

~~The efforts with the constellation of Department of Energy National~~Purchase ~~Laboratories~~Agreement (Los Alamos National Laboratory, LANL; Brookhaven National Laboratory, BNL; National Renewable Energy Laboratory, NREL) continue to gain momentum. This group of leading scientists and engineers is working closely with ~~Advent’s development~~Lincoln and manufacturing teams and are furthering the understanding of breakthrough materials that will advance HT-PEM fuel cells. This next generation HT-PEM is well suited for heavy duty transportation, marine, and aeronautical applications, as well as delivering benefits in cost and lifetime for stationary power systems used in telecom and other remote power markets.Park

On April 10, 2023, Advent ~~and~~entered ~~BASF~~into ~~New~~a ~~Business~~purchase ~~GmbH~~agreement (the “~~BASF~~Prior Purchase Agreement”) ~~signed~~with Lincoln Park, which provided that, upon the terms and subject to the conditions and limitations set forth therein, Advent has the right, but not the obligation, to sell to Lincoln Park up to $50 million worth of shares of its common stock from time to time over the 36-month term of the Purchase Agreement. Concurrently with entering into the Purchase Agreement, Advent also entered into a registration rights agreement with Lincoln Park, pursuant ~~Memorandum~~to which we agreed to register the resale of ~~Understanding~~the ~~(“MoU”)~~shares of our common stock that have been and may be issued to Lincoln Park under the Purchase Agreement pursuant to a registration statement. Upon the execution of the Purchase Agreement, we issued 21,186 shares of common stock to Lincoln Park as consideration for its commitment to purchase shares of our common stock under the Purchase Agreement. Lincoln Park has agreed not to cause or engage in any manner whatsoever, any direct or indirect short selling or hedging of our common stock. As of December 31, 2024, Lincoln Park had sold an aggregate of 10,490 shares for net proceeds to the Company of $5.5 million.

~~On December 13, 2021, it was announced that the MoU aims to develop~~At ~~and increase~~ the ~~manufacturing~~Market ~~scale~~Offering of advanced fuel cell membranes designed for long-term operations under extreme conditions. BASF intends to improve the long-term stability of its Celtec® membrane and to increase production capacity with advanced technical capabilities to enable further improved and competitive Advent fuel cell systems and MEAs. Under the agreement the two companies will explore the implementation of high-volume manufacturing for the Celtec® membranes, utilize Advent’s fuel cell stack and system testing facilities to assess and qualify the new Celtec® membrane for the SereneU (telecom power), M-ZERØ (methane emissions reduction), and Honey Badger (portable power, defense) Advent product families. Furthermore, BASF supports the realization of large-scale Important Projects of Common European Interests (“IPCEIs”) White Dragon and Green HiPo (pending EU approval), through materials for power generation, hydrogen generation, and power storage. The goal of the two projects as submitted by Advent and the White Dragon consortium of companies is to replace Greece’s largest coal-fired power plants with renewable solar energy parks, which will be supported by CO2-free hydrogen production (4.65GW), and fuel cell heat and power production (400MW). In addition, BASF will also evaluate the producibility of the ion-pair membrane developed in collaboration by Advent and the U.S. Department of Energy. Advent has substantial experience in the development of high-temperature PEM fuel cell systems namely for stationary and portable applications as well as critical components such as MEAs and Gas Diffusion Electrodes (“GDEs”). Advent is working to increase the performance and scope of its products to satisfy the requirements of its customers and to address new applications. BASF has substantial experience in the manufacturing and development of proton-conducting membranes, GDEs, HT-PEM MEAs and the pertinent chemicals, catalysts, and compositions for their application in hydrogen separation and fuel cells. BASF is constantly improving the quality, robustness and performance of its products to support growth in fuel cell systems applications.Agreement

38On June 2, 2023, Advent entered into an At The Market Offering Agreement (the “ATM Agreement”) with H.C. Wainwright & Co., LLC, as sales agent (the “Agent”), to create an at-the-market equity program under which it may sell up to $50 million of shares of Advent’s Common Stock from time to time through the Agent (the “ATM Offering”). Under the ATM Agreement, the Agent will be entitled to a commission at a fixed rate of 3.0% of the gross proceeds from each sale of shares under the ATM Agreement.

~~TABLE~~Sales of OFCommon ~~CONTENTS~~Stock, if any, under the ATM Agreement may be made in transactions that are deemed to be “at-the-market equity offerings” as defined in Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”), including sales made by means of ordinary brokers’ transactions, including on the Nasdaq Capital Market, at prevailing market prices at the time of sale or as otherwise agreed with the Agent. Advent has no obligation to sell, and the Agent is not obligated to buy or sell, any of the Common Stock under the Agreement and may at any time suspend offers under the Agreement or terminate the Agreement. The ATM Offering will terminate upon the termination of the ATM Agreement as permitted therein. As of December 31, 2024, the Agent had sold an aggregate of 233,061 shares for net consideration to the Company of $1.6 million.

Common Stock was issued pursuant to Advent’s ~~Launches~~previously ~~New~~filed ~~Product~~Registration ~~Line,~~Statement Mon Form S-~~ZERØ™~~3 ~~Fuel~~(File No. 333-271389) that was declared ~~Cells~~effective on May 2, 2023 and a prospectus supplement and accompanying prospectus relating to ~~Significantly~~the ~~cut~~ATM ~~Methane~~Offering ~~Emissions~~filed inwith ~~North~~the ~~America~~Securities and Exchange Commission (“SEC”) on June 2, 2023.

~~The Advent M-ZERØ™ products, designed specifically to generate power~~Purchase inAgreement remote environments, will offer the ability to drop methane emissions to effectively zero where they replace methane polluting pneumatic injection technology. M-ZERØ™ will initially be deployed mainly in Canada and the United States with ~~the ultimate~~Joseph ~~goal~~Gunnar of& ~~providing remote power to up to 185~~Co.,~~000~~ ~~oil and gas wellheads.~~ LLC

~~Selection~~On December 22, of2023, ~~Wearable~~the ~~Fuel~~Company ~~Cell~~entered ~~for~~into a Securities Purchase Agreement (the ~~DOD~~“Gunnar ~~2021~~Purchase Agreement”) with those ~~Validation~~certain ~~Program~~purchasers named therein (the “Purchasers”) pursuant to which the Company agreed to issue and sell, in a public offering, directly to the Purchasers (the “Registered Direct Offering”), 333,333 shares of common stock. The purchase price per share of Common Stock is $6.00, resulting in gross proceeds of $2,000,000.

~~On March 31, 2021, we announced that UltraCell’s 50 W Reformed~~As ~~Methanol~~of ~~Wearable Fuel Cell Power System (“Honey Badger”) had been selected by~~ the ~~U.S.~~date ~~Department~~ of ~~Defense’s~~filing ~~(“DOD”)~~of ~~National~~our ~~Defense~~2024 ~~Center~~10-K, ~~for~~the ~~Energy~~net ~~and~~proceeds ~~Environment (“NDCEE”)~~ to ~~take~~the ~~part~~Company inare ~~its~~approximately ~~demonstration/validation program for 2021~~$1. ~~The~~8 ~~NDCEE is a DOD program that addresses high-priority environmental~~million, ~~safety,~~after ~~occupational~~deducting ~~health,~~estimated ~~and energy technological challenges that are demonstrated and validated at active installations for military application. UltraCell’s “Honey~~expenses ~~Badger~~payable ~~50”~~by ~~fuel cell is~~ the ~~only~~Company ~~fuel~~associated ~~cell~~with ~~that is part of this program that supports~~ the ~~U.S.~~Registered ~~Army’s~~Direct ~~goal of having a technology-enabled force by 2028~~Offering.

~~UltraCell~~The Company ~~Purchase~~paid ~~Agreement~~Gunnar an aggregate cash fee equal to 9.0% of the gross proceeds of the Registered Direct Offering, and agreed to reimburse Gunnar up to a total of $25,000 for actual fees and expenses of legal counsel and other out-of-pocket expenses.

~~On February 18, 2021, Advent Technologies Inc., entered into a~~Collaboration ~~Membership Interest Purchase Agreement (the “MI Purchase Agreement”)~~ with ~~Bren-Tronics, Inc. (“Bren-Tronics”) and UltraCell, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Bren-Tronics (“UltraCell”). Pursuant to~~ the MIDepartment ~~Purchase Agreement, and subject to the terms and conditions therein, on February 18, 2021, Advent acquired 100%~~ of the issued and outstanding membership interests in UltraCell, for $4 million and a maximum of $6 million upon achievement of certain milestones. Advent also assumed the terms of Bren-Tronics lease for property used in UltraCell’s operations in Livermore, California. Energy

~~Leases~~The efforts with the constellation of Department of Energy National Laboratories (Los Alamos National Laboratory, LANL; Brookhaven National Laboratory, BNL; National Renewable Energy Laboratory, NREL) continue to gain momentum. This group of leading scientists and engineers is working closely with Advent’s development and manufacturing teams and are furthering the understanding of breakthrough materials that will advance HT-PEM fuel cells. This next generation HT-PEM appears to be well suited for heavy duty transportation, marine, and aeronautical applications, as well as delivering benefits in cost and lifetime for stationary power systems used in telecom and other remote power markets.

On February 5, 2021, the Company entered into a lease agreement by and among the Company, in its capacity as tenant, and BP Hancock LLC, a Delaware limited liability company, in its capacity as landlord. The lease provides for the rental by the Company of office space at 200 Clarendon Street, Boston, MA 02116 for use as the Company’s executive offices. Under the terms of the lease, the Company leases 6,041 square feet at an initial fixed annual rent of $456,095. The term of the lease is for five years (unless terminated as provided in the lease). The Company provided security in the form of a security deposit in the amount of $114,023.50

OnTable ~~March 8, 2021, the Company entered into a lease for 21,401 square feet as a product development and manufacturing center at Hood Park in Charlestown, MA. Under the terms~~ of the lease, the Company will pay an initial fixed annual rent of $1,498,070. The lease has a term of eight years and five months, with an option to extend for five years and is expected to commence in August 2022. The Company provided security in the form of a security deposit in the amount of $750,000, upon commencement of the lease.Contents

~~On August 31, 2021, the Company through its wholly owned subsidiary,~~Agreements ~~FES,~~with ~~entered~~Hyundai ~~into~~Motor ~~a lease agreement by and among the~~ Company, in its capacity as lessee, and fischer group SE & Co. KG, having its registered seat in Achern, in its capacity as lessor. The lease provides for the rental by the Company of office space, workspace and outdoor laboratory at 77855 Achern, Im Gewerbegebiet 7 for use by FES. Under the terms of the lease, the Company leases 1,017 square feet at a monthly basic rate of Euros 7,768 plus VAT. The lessor has granted the lessee an option right to extend the lease by another five years at the terms and conditions of the lease agreement (~~option term~~“Hyundai”). The option right must be exercised by written declaration of the lessee and delivered to the lessor not later than ninety days prior to the expiration of the fixed term. The lessee is entitled to terminate the lease early (even during fixed lease term or option term), to the end of each calendar quarter with a notice period of four months. The lessee is obliged to furnish security to the lessor upon occupying the leased premises. The Company provided security in the form of a parent guarantee for a maximum amount of Euro 30,000.

~~Comparability~~On April 6, 2022, Advent announced the signing of ~~Financial~~a ~~Information~~technology assessment, sales, and development agreement with Hyundai, a leading multinational automotive manufacturer offering a range of world-class vehicles and mobility services in over 200 countries. Advent and Hyundai aim to deliver green energy solutions to current high carbon applications, using fuel cell technology. Under the agreement, Hyundai will provide catalysts to Advent for evaluation in its proprietary MEAs, while Advent intends to support Hyundai in fulfilling its fuel cell project needs, through:

~~Advent’s~~● ~~results~~Developing ofinks ~~operations~~ and ~~statements~~structures ofusing ~~assets~~Hyundai ~~and liabilities~~catalysts, ~~may~~which ~~not~~will then be ~~comparable~~evaluated ~~between~~by ~~periods~~Hyundai. asFollowing aevaluation, ~~result~~Hyundai ofwill ~~the~~determine ~~Business~~whether ~~Combination~~their own or standard catalysts will be used for this project.

39 ● Supplying MEAs throughout the development/commercialization cycle (“Advent MEAs”) for testing, evaluation, and optimization under conditions set by Hyundai.

~~TABLE~~● OFAssisting ~~CONTENTS~~Hyundai with the use and specifications of MEAs as well as their implementation into Hyundai’s designs.

On March 23, 2023, Hyundai announced a successful technology assessment with Advent and following its success, Advent and Hyundai have entered into a Joint Development Agreement (“JDA”). Under the agreement, Hyundai and Advent will work together to further develop HMC-Advent Ion Pair™ MEA, establish commercial criteria for MEA supply, and evaluate Advent’s advanced fuel cell technology for Hyundai’s heavy-duty and/or stationary application. Additionally, the parties will introduce advanced cooling technologies for mobility HT-PEM fuel cell stacks. Advent will work closely as Hyundai evaluates these stack cooling technologies and ensure optimal performance under different operating conditions.

This partnership builds upon a commitment from both companies to develop sustainable energy solutions for carbon-intensive applications. Hyundai aims to accelerate the establishment of a hydrogen-based society based on its vision, Progress for Humanity, and this JDA aligns with that vision. The synergy generated by combining the two companies’ advanced technology in this JDA is expected to revolutionize the global MEA market by providing significant improvement in lifetime and an increase in power density versus current HT-PEM MEAs.

BASF Environmental Catalyst and Metal Solutions (“BASF”)

On May 9, 2023, Advent and BASF, a global leader in precious metals and catalysis, concluded on the terms of a new agreement to join efforts in building a closed loop component supply chain for fuel cells and enter discussions to extend the partnership into the field of water electrolysis. For 20 years, BASF has been a leader in membrane and MEA technology for HT-PEM fuel cells with a strong foundation in precious metal services and catalysis. HT-PEM fuel cells operate at 120 to 180°C, offer a broad operating window and tolerate impurities in the hydrogen fuel source. The fuel cells also enable simplified cooling and need no humidification. Advent offers competitive fuel cell systems for stationary and portable applications based on methanol and on-site reforming. In the future, HT-PEM fuel cells will also be available for heavy duty mobility and marine power. The scope of the agreement includes BASF’s full portfolio of products and services to enable circularity in key materials. Both companies will cooperate on BASF’s latest membrane development, Celtec®-Z, and the new Ion Pair™ MEA by Advent, aiming for improved performance, lifetime and cost competitiveness.

Advent and Safran Power Units Sign MoU to Advance HT-PEM Fuel Cell Technology for the Aerospace Sector

On May 31, 2023, Advent signed a memorandum of understanding (“MoU”) with Safran Power Units, a leader in auxiliary power systems and turbojet engines. Leveraging Advent’s proprietary Ion Pair™ MEA technology, and Safran Power Units’ knowledge and capabilities in aerospace, this new collaboration seeks to advance the development of next-generation HT-PEM fuel cell technology, specifically for the aerospace sector.

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HT-PEM enables more efficient heat management versus low temperature-PEM (“LT-PEM”). HT-PEM is more adapted for applications requiring high amounts of power combined with strong integration constraints such as aviation. HT-PEM is also more robust and can withstand tougher operating conditions, such as extreme temperatures and pollution, versus LT-PEM.

As part of the MoU, Advent and Safran Power Units are exploring a joint development agreement for the advancement of HT-PEM fuel cells in aviation and for enhancing Advent’s supply capability.

As of December 31, 2024, there was no new activity in respect to this MoU.

Launch of the Honey Badger 50™ Fuel Cell System

On August 4, 2022, we announced the launch of our HB50 power system, a compact portable fuel cell system and quiet power supply for use in off-grid field applications such as military and rescue operations. The launch of Advent’s portable power system coincided with the Company’s fulfilment of its first shipment order from the U.S. Department of Defense. The HB50 power system can be fueled by biodegradable methanol, allowing near silent generation of up to 50W of continuous power with clean emissions. Designed for covert operations, HB50 can easily power radio and satellite communications gear, remote fixed and mobile surveillance systems, and laptop computers along with more general battery charging needs. HB50 is a unique technology that can provide 65% of weight savings versus batteries over a typical 72-hour mission. The weight savings benefit increases further for longer missions.

HB50’s unique design allows it to be used in soldier-worn configurations or operated inside a portable backpack or vehicle while charging batteries and powering soldier systems, while its thermal features allow it to operate within an ambient temperature range of -20°C to +55°C. Aside from its optimized compatibility with Integrated Visual Augmentation System (“IVAS”), HB50 can also power devices such as high frequency radios like the model 117G, as well as B-GAN and StarLink terminals. HB50’s durability allows it to be easily deployed in challenging conditions and climates while supporting mission mobility for three to seven days without the need to re-supply.

Since Honey Badger’s fuel cell technology can run on hydrogen or liquid fuels, the system can operate at a fraction of the weight of traditional military-grade batteries to meet the U.S. Department of Defense’s continuously evolving needs for ‘on-the-go’ electronics needs. As military adoption and use of IVAS equipment continues to evolve, the highly portable lightweight power solutions like Honey Badger and HB50 will become a mission critical necessity.

In September 2023, Advent secured a new $2.2 million contract with the US DoD. This milestone achievement comes under the General Technical Services prime contract and will play a crucial role in supporting the demanding defense mission requirements of the US Army. This contract is the continuation of a series of past contracts with the US DoD and its primary objective is to further optimize Advent’s proprietary Honey Badger 50™ portable fuel cell system by integrating the Company’s innovative Ion Pair MEA technology. Upon the completion of this new 12-month contract, Advent and the US DoD aim to reinforce their long-term collaboration by focusing on the manufacturing process of the enhanced HB50 fuel cell system, that will enable high-volume production manufacturing capacity. MEAs form the heart of the fuel cell, and their performance determines the lifetime, efficiency, weight, and to a large extent, the cost of the end electrochemistry products. Advent’s Ion Pair MEA technology is anticipated to significantly enhance HB50’s performance, resulting in higher power density and improved compact packaging, making it an ideal solution for off-grid field applications, including military and rescue operations.

In December 2023, Advent secured a new $2.8 million contract with the US DoD. Under this new defense contract which comes under the umbrella of the Envision Innovative Solutions (‘‘EIS’’), Advent will develop advanced manufacturing processes to enable a substantial increase in the production capacity while maintaining quality of the HB50 system. This new project is aligned with Advent’s and the US DoD’s shared objective to strengthen their long-term collaboration and transform HB50 into a portable and clean source of power.

As of December 31, 2024, Advent continues to work with the US DoD to advance the HB50 technology.

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Nasdaq Deficiency Letters

On May 24, 2023, the Company received a letter from Nasdaq indicating that the bid price of the Common Stock had closed below $1.00 per share for 30 consecutive business days and, as a result, the Company was not in compliance with Nasdaq’s Minimum Bid Requirement.

On May 13, 2024, the Company effectuated the Reverse Stock Split, and our Common Stock began trading on a split-adjusted basis on the Nasdaq Capital Market at the opening of trading on May 14, 2024, in an effort to comply with the Minimum Bid Requirement. The Company has since received confirmation from Nasdaq that it has met the Minimum Bid Requirement.

On April 17, 2024, we received a letter from Nasdaq notifying the Company that it is not in compliance with Timely Report Requirement due to the fact that the 2023 10-K was not filed by the required due date of March 31, 2024. Additionally, on May 24, 2024, we received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its First Quarter 10-Q by the required due date of May 14, 2024. Further, on November 22, 2024, we received a letter from Nasdaq notifying the Company that it is not in compliance with the Timely Reporting Requirement due to the fact that the Company did not file its Third Quarter 10-Q by the required due date of November 20, 2024. On April 16, 2025, the Company also received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth in Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its 2024 10-K by the required due date of April 16, 2025. Lastly, on May 22, 2025, the Company received a letter from Nasdaq notifying the Company that it is not in compliance with the periodic requirements for continued listing set forth in Nasdaq Listing Rule 5250(c)(1) due to the fact that the Company did not file its Q1 2025 10-Q by the required due date of May 15, 2025. The Company submitted compliance plans to Nasdaq setting forth its plan to file 2023 10-K, the First Quarter 10-Q, the Third Quarter 10-Q, the 2024 10-K and the Q1 2025 10-Q. The Company filed its 2023 10-K on August 13, 2024, its First Quarter 10-Q on October 15, 2024, its Third Quarter 10-Q on December 27, 2024, its 2024 10-K on June 6, 2025 and its Q1 2025 10-Q on June 30, 2025.

Additionally, on October 18, 2024, we received a letter from Nasdaq notifying the Company that since the Company’s Form 10-Q for the period ended June 30, 2024, reported stockholders’ equity of ($2,879,000), and as of the date of such letter the Company did not meet the alternatives of market value of listed securities or net income from continuing operations, the Company is no longer in compliance with Nasdaq’s Listing Rule requiring the Company to maintain a minimum of $2,500,000 in stockholders’ equity for continued listing. The Company submitted a compliance plan and supplement to Nasdaq setting forth its plan to increase its stockholders’ equity, and on April 16, 2025, received a letter from Nasdaq confirming that the Company had regained compliance with the minimum stockholders’ equity rule for continued listing.

New Board Member

On December 31, 2024, the Company’s shareholders elected Robert Schwartz as a Class I director of the Company, with a term expiring at the 2027 annual meeting of the Company’s stockholders or until his successor is duly elected and qualified in accordance with our second amended and restated certificate of incorporation and amended and restated bylaws, or his earlier death, resignation or removal.

Termination of Former Chief Executive Officer

On October 24, 2024, the Board approved the termination of the employment of Vassilios Gregoriou, the Chief Executive Officer, Acting Chief Financial Officer, for cause, effective immediately. Mr. Gregoriou was also removed as Chairman of the Board of Directors.

Advent Technologies A/S declared bankrupt

On July 25, 2024, Advent Technologies A/S was declared bankrupt by the court in Aalborg, Denmark. The petition was brought by IDA, the union of engineers with a claim for €402,000. As the Company did not have the ability to pay the full amount due, the Danish court declared Advent Technologies A/S bankrupt. Advent Technologies A/S and its wholly-owned subsidiary Green Energy Philippines, Inc. will be liquidated by the court appointed trustee to settle all claims under the bankruptcy. The Company anticipates it will receive no residual assets from the bankruptcy. The remainder of the Company’s legal entities have no plans to declare bankruptcy and will continue as going concern entities.

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Arbitration Award

On August 16, 2024, the Company was informed that an arbitration decision and award was decided in favor of F.E.R. in the amount of approximately €4.5 million. The Company appealed the decision and instructed its counsel to file a motion with the Higher Regional Court of Frankfurt to set aside the arbitral award. On July 1, 2025, the Company entered into a settlement agreement and release (the “Settlement Agreement”) with F.E.R.. Pursuant to the terms of the Settlement Agreement, the Company has agreed to pay F.E.R. €5,366,625.55 with such payment to be made in monthly installments of €35 thousand beginning on September 1, 2025. The Company will be entitled to a reduced settlement amount totaling €4,366,625.55 if payment is made by no later than June 30, 2026. In exchange for such reduced settlement amount, both Parties agreed to a mutual release of claims against the other Party.

Key Factors Affecting Our Results

Advent believes that its performance and future success depend on several factors that present significant opportunities for Advent but also pose risks and challenges, including those discussed below.

Increased Customer Demand

Based on conversations with existing customers and incoming inquiries from new customers, Advent anticipates substantial increased demand for its fuel cell systems and MEAs from a wide range of customers as it scales up its production facilities and testing capabilities, and as the awareness of its MEA capabilities becomes widely known in the industry. Advent expects both its existing customers to increase order volume, and to generate substantial new orders from major organizations, with some of whom it is already in discussions regarding prospective commercial partnerships and joint development agreements. As of December 31, ~~2021~~2024, Advent was still generating a low level of revenues compared to its future projections and has not made any commercial sales to these major organizations.

Successful development of the Advanced MEA product

Advent’s future success depends in large part on the increasing integration of the hydrogen fuel cell into the energy transition globally over the next decade. In order to become cost-competitive with existing renewable power generation and energy storage technology and achieve widespread adoption, fuel cells will need to achieve substantial improvement in the cost/kw performance ratio delivered to prospective fuel cell customers, predominantly OEMs, System Integrators and major energy companies. Advent expects to play an important enabling role in the adoption of hydrogen fuel cells, as its MEA technology is the critical determining factor in the cost/kw performance ratio of the fuel cells. In partnership with the Los Alamos National Laboratory, Advent is currently developing its next generation MEA technology (“Advanced MEA”) which is anticipated to deliver as much as three times the power output of its current MEA product. While Advent is already projecting being able to pass through ~~substantial~~ cost benefits to its customers through economies of scale as it increases MEA production, the successful development of the Advanced MEA will be an important factor in delivering the required improvement in cost/kw performance to Advent’s customers.

Basis of Presentation

Advent’s consolidated financial statements have been prepared in accordance with U.S. GAAP. The Company has determined that it operates in one reportable segment. See Note 1 “Basis of Presentation” in the ~~accompanying~~Notes ~~consolidated~~to ~~financial~~the ~~statements~~Consolidated ~~for~~Financial ~~more~~Statements ~~information~~included with the 2024 10-K.

Components of Results of Operations

Revenue

Revenues consist of sales of goods (MEAs, membranes, fuel cell stacks, fuel cell systems and electrodes). ~~Advent~~and ~~expects~~servicing ~~revenues~~of tothose ~~increase~~systems, ~~materially~~as well as engineering fees and berevenue ~~weighted~~from ~~towards~~Joint ~~fuel~~Development ~~cell~~Agreements ~~systems~~(JDAs) and ~~MEA~~Technology ~~sales~~Assessment ~~over~~Agreements ~~time,~~(TAAs) inwith ~~line~~world-leading OEMs ~~with~~for the ~~projected~~development ~~increase~~of injoint ~~MEA~~products. ~~production~~Advent inexpects ~~response~~revenues to ~~customer~~increase ~~demand~~materially and be weighted towards JDAs and TAAs over time.

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Cost of Revenues

Cost of revenues consists of consumables, raw materials, processing costs and direct labor costs associated with the assembly, manufacturing, and ~~manufacture~~servicing of MEAs, membranes, fuel cell stacks and systems and electrodes. Advent expects its cost of revenues to ~~increase~~decrease ~~substantially~~as inthe focus ~~line~~on ~~with~~providing ~~increased~~services ~~production~~under Joint Development Agreements and Technology Assessment Agreements and its shift from product sales. Advent also recognizes slow moving inventory reserve in cost of revenues. Advent recognizes cost of revenues in the period that revenues are recognized.

Income from Grants

Income from grants consists of cash subsidies received from research agencies and other national and international organizations in support of Advent’s research and development activities. Advent expects to continue to be eligible for grant income and remains in discussion with a number of prospective grantors in relation to a number of product development activities.

Research and Development Expenses

Research and development expenses consist of costs associated with Advent’s research and development activities, such as laboratory costs and sample material costs. Advent expects its research and development activities to increase substantially as it invests in improved technology and products.

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Administrative and Selling Expenses

Administrative and selling expenses consist of travel expenses, indirect labor costs, fees paid to consultants, third parties and service providers, taxes and duties, legal and audit fees, depreciation, business development salaries and limited marketing activities, and incentive and stock-based compensation expense. Advent expects administrative and selling expenses to increase in line with ~~MEA~~ production and revenue as the business scales up, and as a result of operating as a public company, including compliance with the rules and regulations of ~~the~~ the SEC, legal, audit, additional insurance expenses, investor relations activities and other administrative and professional services. ~~Depreciation is also expected to increase as the Company invests in fixed assets in support of the scale-up of the business.~~

Other Income / (Expenses), Net

Other income / (expenses) consist of additional de minimis incidental income / (expenses) incurred by the business. These income / (expenses) are expected to remain at a de minimis level in the future.

Change in Fair Value of Warrant Liability

Change in fair value of warrant liability amounting to nil and $220.7 1 million for the ~~year~~three and six months ended ~~December~~June 3130, ~~2021~~2025 and 2024, respectively, represents the change in fair value of the Private Placement Warrants and Working Capital Warrants ~~from February 4, 2021 to December 31, 2021~~.

Finance income ~~Costs~~/ (expenses), Net

Finance income ~~costs~~/ (expenses) consist mainly of bank ~~charges.~~and ~~Finance~~interest ~~costs are not anticipated to increase materially as Advent is not intending to take on substantial borrowings at the corporate level in the near future~~charges.

Foreign Exchange ~~exchange~~Gains ~~differences~~/ (Losses), ~~net~~Net

Foreign exchange ~~differences,~~gains ~~net~~/ (losses) consists of foreign exchange gains or losses on transactions denominated in foreign currencies and on translation of monetary items denominated in foreign currencies. As ~~the~~Advent ~~Company~~ scales up, ~~its~~our foreign exchange exposure is likely to increase given its revenues are denominated in both euros and dollars, and a portion of the ~~Company’s~~our costs are denominated in euros.

Amortization of ~~intangibles~~Intangibles

The ~~intangible~~amortization ~~assets~~expense offor ~~$4.7 million recognized on~~ the ~~acquisition of~~intangible ~~UltraCell~~assets isfor the ~~Trade~~six ~~Name~~months ~~“UltraCell”~~ended ~~($0.4 million)~~June ~~and~~30, ~~the~~2025 ~~Patented~~and ~~Technology~~2024 (was $414.~~3 million).~~0 ~~The~~thousand ~~Trade~~and ~~Name has an indefinite useful life while the Patented Technology has a useful life of 10 years, for which amortization expense of~~ $(02.4)0 ~~million has been recognized for the period from the acquisition date of UltraCell to December 31~~thousand, ~~2021~~ respectively.

The intangible assets of $19.8 million recognized on the acquisition of SerEnergy and FES are the Patents amounting to $16.9 million, the Process know-how (IPR&D) amounting to $2.6 million and the Order backlog amounting to $0.3 million. The Patents have a useful life of 10 years, the Process know-how has a useful life of 6 years and the Order backlog has a useful life of 1 year. Amortization expense of $(0.8) million has been recognized in relation to these intangibles for the period from the acquisition date of SerEnergy and FES to December 31, 2021. 55

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Income taxes

~~Income~~During ~~taxes~~the ~~amounting~~three toand ~~$0.9 million~~six ~~for~~months ~~the~~ended ~~year~~June ~~ended~~30, ~~December 31~~2025, ~~2021~~the ~~mainly~~Company ~~relates~~recorded ~~to current~~ income tax ~~benefit~~expense of ~~its~~nil ~~subsidiary~~and ~~SerEnergy~~$(1) thousand. During the three and ~~deferred~~six ~~income~~months ~~tax~~ended ~~benefit~~June on30, ~~tax~~2024, ~~losses~~the ofCompany recorded ~~its~~income ~~subsidiary~~tax ~~FES~~benefit ~~and~~of onnil ~~intangible~~and ~~assets~~$0.1 ~~recognized~~million, ~~upon~~respectively, ~~the~~mainly ~~acquisition~~related ofto ~~SerEnergy~~net ~~and~~operating ~~FES.~~loss carryforwards.

41As of June 30, 2025 and December 31, 2024, the Company provided a valuation allowance to offset the deferred tax asset related to the net operating loss carryforwards.

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Results of Operations

Comparison of the ~~Years~~Three Months Ended ~~December 31~~June 30, ~~2021~~2025 ~~and 2020~~to Three Months Ended June 30, 2024

The following table sets forth a summary of our consolidated results of operations for the ~~years~~three months ended ~~December~~June 3130, ~~2021~~2025 and ~~2020~~2024, and the changes between periods.

		Years Ended December 31,
	Three months ended June 30, (Unaudited)
		2021		2020			$ change			% change
(Amounts in thousands, except share and per share amounts)	2025			2024				$ change			% change
Revenue		$7,068,842		$882,652			$6,186,190			700.9%
Revenue, net	$	99		$	654			$	(555	)		(84.9	)%
Cost of revenue		(5,406,216)		(513,818)			(4,892,398)			952.2%
Cost of revenues		(392	)		(83	)			(309	)		372.3	%
Gross profit		1,662,626		368,834			1,293,792			350.8%
Gross profit / (loss)		(293	)		571				(864	)		(151.3	)%
Income from grants		~~829,207~~1		~~206,828~~	424		~~622,379~~		(423	~~300.9%~~)		(99.8	)%
Research and development expenses		(~~3,540,540)~~342	)	~~(102,538)~~	(695	)	~~(3,438,002)~~		353	~~3,352.9%~~		(50.8	)%
Administrative and selling expenses		(411,~~876,741)~~956	)	~~(3,546,856)~~	2,374		~~(38,329,885)~~		(4,330	~~1,080.7%~~)		(182.4	)%
Amortization of intangible assets		(1,184,830)		—			(1,184,830)			N/A
Amortization of intangibles		(7	)		(1	)			(6	)		600.0	%
Operating loss		(44,110,278)		(3,073,732)			(41,036,546)			1,335.1%
Credit loss – customer contracts		(328	)		-				(328	)		N/A
Fair value change of warrant liability		22,743,057		—			22,743,057			N/A
Operating loss		(2,925	)		2,673				(5,598	)		(209.4	)%
Finance expenses, net		(51,561)		(5,542)			(46,019)			830.4%
Finance income / (expenses), net		(325	)		(54	)			(271	)		501.9	%
Foreign exchange losses, net		(42,708)		(26,072)			(16,636)			63.8%
Foreign exchange gains / (losses), net		293			(156	)			449			(287.8	)%
Other income (expenses), net		15,638		(15,696)			31,334			(199.6)%
Loss contingency		(840	)		36				(876	)		(2,433.3	)%
Loss before income taxes		(21,445,852)		(3,121,042)			(18,324,810)			587.1%
Net gains / (losses) on disposal/write-off property, plant and equipment and intangible assets		-			(12,714	)			12,714			(100.0	)%
Income taxes		922,510		—			922,510			N/A
Other income / (expenses), net		-			2				(2	)		(100.0	)%
Net loss		$(20,523,342)		$(3,121,042)			$(17,402,300)			557.6%
Loss before income tax		(3,797	)		(10,213	)			6,416			(62.8	)%
Net loss per share
Income tax (expense)		-			-				-			N/A
Basic loss per share		$(0.45)		$(0.15)			$(0.30)			N/A
Net loss from continuing operations	$	(3,797	)	$	(10,213	)		$	6,416			(62.8	)%
Basic weighted average number of shares		45,814,868		20,518,894			N/A			N/A
Income (loss) from discontinued operations		-			(1,060	)			1,060			(100.0	)%
Diluted loss per share		$(0.45)		$(0.15)			$(0.30)			N/A
Net loss		(3,797	)		(11,273	)			7,476			(66.3	)%
Diluted weighted average number of shares		45,814,868		20,518,894			N/A			N/A
Net loss per share
Basic loss per share from continuing operations		(1.42	)		(3.88	)			2.46			N/A
Basic loss per share from discontinued operations		N/A			(0.40	)			0.40			N/A
Basic loss per share		(1.42	)		(4.28	)			2.86			N/A
Basic weighted average number of shares		2,665,089			2,634,179				N/A			N/A
Diluted loss per share from continuing operations		(1.42	)		(3.88	)			2.46			N/A
Diluted loss per share from discontinued operations		N/A			(0.40	)			0.40			N/A
Diluted loss per share		(1.42	)		(4.28	)			2.86			N/A
Diluted weighted average number of shares		2,665,089			2,634,179				N/A			N/A

~~Revenue~~56

~~Our~~Table total revenue from product sales increased by approximately $6.2 million or 700.9% from approximately $0.9 million in the year ended December 31, 2020 to approximately $7.1 million in the year ended December 31, 2021. The increase in revenue was related to a) increased demand from customers for Advent’s MEAs and other products, as a result of Advent’s customers increasing their own testing and usage of Advent’s products, b) revenue from UltraCell’s operations (acquired on February 18, 2021) and c) revenue from SerEnergy and FES’s operations (acquired on August 31, 2021).Contents

Revenue, net

Our total revenue decreased by approximately $0.6 million from approximately $0.7 million in the three months ended June 30, 2024 to approximately $0.1 million in the three months ended June 30, 2025. The decrease was driven by an increase in contract liabilities related to our services provided under Joint Development Agreements (JDAs) and Technology Assessment Agreements (TAAs) in the three months ended June 30, 2025 which are expected to be delivered later in 2025.

Cost of Revenues

Cost of revenues increased by approximately $40.9 3 million from approximately $0.5 1 million in the ~~year~~three months ended ~~December~~June 3130, ~~2020~~2024 to approximately $50.4 million in the ~~year~~three ~~ended~~months ~~December~~ended June 3130, ~~2021~~2025. The increase in cost of revenues was ~~directly~~ related to ~~the~~an ~~increased~~increase ~~revenues~~in ~~and~~fixed ~~the~~costs ~~requirement~~during ~~for~~the ~~increased production of MEAs and fuel cell systems to satisfy customer demand, as well as, cost of revenues attributed to UltraCell’s, SerEnergy’s and FES’s operations~~period.

~~Gross~~Income ~~profit, which is revenue, net minus the cost of revenue, increased to $1.7 million in the year ended December 31, 2021~~ from ~~$0.4 million in the year ended December 31, 2020.~~Grants

Our income from grants decreased by approximately $0.4 million from approximately $0.4 million in the three months ended June 30, 2024 to approximately $1 thousand in the three months ended June 30, 2025. The decrease was driven by an increase in deferred revenue from grants in the three months ended June 30, 2025 which is expected to be recognized later in 2025.

Research and Development Expenses

Research and development expenses were approximately $0.3 million and $0.5 7 million in the ~~year~~three months ended ~~December~~June 3130, ~~2021,~~2025 ~~primarily related to the Company’s cooperative research~~ and ~~development~~2024, ~~agreement with the U.S. Department of Energy~~respectively, asprimarily ~~well~~related asto ~~the~~internal research and development costs ~~of SerEnergy and FES in the four-month period from September 1, 2021 to December 31, 2021~~.

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Administrative and Selling Expenses

Administrative and selling expenses were approximately $412.9 0 million in the ~~year~~three months ended ~~December~~June 3130, ~~2021~~2025, and ~~$3.5 million~~a ~~in the year ended December 31, 2020. The increase was primarily due to one-time transaction costs following the Business Combination amounting to~~ $52.9 4 million, ~~the~~reversal ~~increased personnel~~ in the ~~Greece~~ ~~and~~three ~~Boston~~months ~~offices,~~ended ~~the recognition of stock-based compensation expense amounting to $7.7~~June ~~million~~30, ~~incentive compensation costs, administrative and selling expenses associated with being a public company, costs of the SerEnergy/FES businesses post-acquisition and a non-recurring $2~~2024.~~4 million charge for executive severance.~~

Sublease income

The Company earned sublease income of $0.1 million in the six months ended 2024. The sublease was terminated in April 2024.

Credit Loss – Customer Contracts

We recognized credit losses on customer contracts of $0.5 million during the three months ended June 30, 2025, which was an increase of $0.5 million from June 30, 2024.

Change in fair value of Warrant Liability

The change in fair value of warrant liability amounting to nil and $220.7 1 million was due to the change in fair value of the Private Placement Warrants and Working Capital Warrants ~~from~~for the ~~February~~six months ended June 430, ~~2021~~2025 toand ~~December 31~~2024, ~~2021~~respectively.

Finance income / (expenses), net

The Company accrued interest expense of $(0.6) million related to the short term note payable and the loss contingency accrued in relation to the decision of F.E.R. in the amount of approximately €4.5 million for the six months ended June 30, 2025.

The Company accrued interest expense of $(0.3) million related to the loss contingency accrued in relation to the decision of F.E.R. in the amount of approximately €4.5 million for the six months ended June 30, 2024.

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Loss contingency

Net gains/ (losses) on disposal/write-offs of property, plant and equipment and intangible assets

We recognized losses of $(12.7) million during the six months ended June 30, 2025, which is an increase of $(12.7) million from June 30, 2024. The losses primarily relate to the disposal of certain coating machines at the Hood Park facility and the termination of the Hood Park lease.

Liquidity and Capital Resources

AsAt ~~of March~~June 3130, ~~2022,~~2025 ~~Advent’s~~and ~~existing~~for ~~cash~~the ~~resources~~six ~~and~~months ~~projected~~then ~~cash~~ended, ~~flows~~the ~~are~~Company ~~anticipated~~had to$0.1 bemillion ~~sufficient~~in tocash ~~support~~and ~~planned~~cash ~~operations~~equivalents, ~~for~~used ~~the~~$1.2 ~~next~~million 12of ~~months.~~cash ~~This~~in isoperating ~~based~~activities, onhad ~~the~~$1.5 ~~amount~~million in ofcurrent ~~cash~~assets weand ~~raised~~$29.4 million in ~~the~~current ~~Business~~liabilities, ~~Combination~~leaving ~~and~~the ~~projected~~Company ~~results~~a ~~over~~working ~~the~~capital ~~next~~deficit 12of ~~months~~$(27.8) million.

~~The~~A major ~~following~~financial ~~table~~challenge ~~sets~~and ~~forth~~significant risk facing the Company is a ~~summary~~lack of ~~our~~positive ~~consolidated~~cash flow and liquidity. The Company’s ability to meet its liquidity needs will largely depend on its ability to raise capital in the very short term and generate cash in the ~~flows~~future. ~~for~~If the ~~years~~Company ~~ended~~is ~~December 31~~unable to obtain sufficient funding, ~~2021~~it could be required to delay its development efforts, limit activities, and ~~2020~~further reduce research and development costs, which could adversely affect its business prospects and delivery of contractual obligations. A cash shortfall at any point in time over the ~~changes~~next ~~between~~twelve ~~periods~~months could result in the Company failing to meet its overdue and current obligations which could trigger action against the Company and/or its subsidiaries for liquidation by employees, authorities, or creditors. Because of the uncertainty in securing additional funding, delays in growth of revenue, failure to materialize cost-cutting efforts and the insufficient amount of cash and cash equivalents as of the consolidated financial statement filing date, management has concluded that substantial doubt exists with respect to the Company’s ability to continue as a going concern for one year from the date the consolidated financial statements are issued.

	Years Ended December 31,
	2021	2020	$ change	% change
Net Cash used in Operating Activities	$(35,837,000)	$(1,425,068)	$(34,411,932)	2,414.8%

Cash Flows from Investing Activities:
Proceeds from sale of property and equipment	6,970	—	6,970	N/A
Purchases of property and equipment	(3,920,470)	(122,508)	(3,797,962)	3,100.2%
Purchases of intangible assets	(17,747)	—	(17,747)	N/A
Advances for the acquisition of property and equipment	(2,200,158)	—	(2,200,158)	N/A
Acquisition of a subsidiary, net of cash acquired	(19,425,378)	—	(19,425,378)	N/A
Net Cash used in Investing Activities	$(25,556,783)	$(122,508)	$(25,434,275)	20,761.3%

Cash Flows from Financing Activities:
Business Combination and PIPE financing, net of issuance costs paid	141,120,851	—	141,120,851	N/A
Proceeds of issuance of preferred stock	—	1,430,005	(1,430,005)	(100.0)%
Proceeds from issuance of non-vested stock awards	—	21,756	(21,756)	(100.0)%
Repurchase of shares	—	(69,431)	69,431	(100.0)%
Proceeds of issuance of common stock and paid-in capital from warrants exercise	262,177	—	262,177	N/A
State loan proceeds	118,274	—	118,274	N/A
Repayment of convertible promissory notes	—	(500,000)	500,000	(100.0)%
Net Cash provided by Financing Activities	$141,501,302	$882,330	$140,618,972	15,937.2%

Net increase in cash and cash equivalents	$80,107,519	$(665,246)	$80,772,765	(12,141.8)%
Effect of exchange rate changes on cash and cash equivalents	(858,823)	(18,035)	(840,788)	4,662.0%
Cash and cash equivalents at the beginning of year	515,734	1,199,015	(683,281)	(57.0)%
Cash and cash equivalents at the end of year	$79,764,430	$515,734	$79,248,696	15,366.2%

The following table sets forth a summary of our consolidated cash flows for the six months ended June 30, 2025 and 2024, and the changes between periods.

	Six Months Ended June 30, (Unaudited)
(Amounts in thousands)	2025			2024			$ change			% change
Net Cash used in Operating Activities	$	(1,159	)	$	(4,001	)	$	2,842			(71.0	)%

Cash Flows from Investing Activities:
Proceeds from sale of property and equipment		-			300			(300	)		(100.0	)%
Purchases of property and equipment		(5	)		(28	)		23			(82.1	)%
Purchases of intangible assets		(24	)		-			(24	)		N/A
Net Cash provided by / (used in) Investing Activities	$	(29	)	$	272		$	(301	)		(110.7	)%

Cash Flows from Financing Activities:
Proceeds from issuance of common stock and paid-in capital		-			282			(282	)		(100.0	)%
Repayments of debt		(1,442	)		-			(1,442	)		N/A
Proceeds from borrowings		2,335			-			2,335			N/A
Net cash provided by Financing Activities	$	893		$	282		$	611			216.7	%

Net decrease in cash, cash equivalents, restricted cash and restricted cash equivalents	$	(295	)	$	(3,447	)	$	3,152			(91.4	)%
Effect of exchange rate changes on cash, cash equivalents, restricted cash and restricted cash equivalents		(11	)		(7	)		(4	)		57.1	%
Net cash provided by / (used in) discontinued operations:
Cash used in operating activities		-			(816	)		816			(100.0	)%
Cash provided by financing activities		-			540			(540	)		(100.0	)%
Net cash used in discontinued operations		-			(276	)		276			(100.0	)%
Net decrease in cash and cash equivalents		(306	)		(3,730	)		3,424			(91.8	)%
Cash and cash equivalents at the beginning of period		381			4,412			(4,031	)		(91.4	)%
Cash and cash equivalents at the end of period	$	75		$	682		$	(607	)		(89.0	)%

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Cash flows used in Operating Activities

Advent’s cash flows ~~used~~from in operating activities reflect the income statement position adjusted for working capital movements in current assets and liabilities. As Advent grows, it expects that operating cash flows will be affected by increased working capital needs to support growth in personnel-related expenditures and fluctuations in accounts receivable, inventory, accounts payable and other current assets and liabilities.

43Net cash used in operating activities was approximately $(1.2) million and $(4.0) million for the six months ended June 30, 2025 and 2024, respectively, which related to outflows in connection with administrative and selling expenses, research and development expenses, and costs associated with insurances services and other personnel costs.

~~TABLE~~Cash OFFlows ~~CONTENTS~~provided by / (used in) Investing Activities

~~affected~~Advent’s bycash ~~increased~~flows ~~working~~provided ~~capital~~by ~~needs~~/ to(used in) ~~support~~investing ~~growth~~activities inwas ~~personnel-related expenditures~~approximately $(0.1) million and ~~fluctuations~~$0.3 inmillion ~~accounts~~for ~~receivable~~the six months ended June 30, ~~inventory~~2025 and 2024, ~~accounts~~respectively, and ~~payable~~which mostly related to the acquisition and ~~other~~sale ~~current~~of ~~assets~~plant and ~~liabilities~~equipment, respectively.

~~Net~~Cash ~~cash~~Flows ~~used~~provided inby ~~operating~~Financing activities was approximately $(35.8) million for the year ended December 31, 2021, which related to outflows in connection with one-time transaction costs, administrative and selling expenses, research and development expenses, and costs associated with insurances services and other consulting services.Activities

~~Net~~Advent’s cash ~~used~~flows inprovided ~~operating~~by financing activities was approximately $(10.4) 9 million for the ~~year~~six months ended ~~December~~June 3130, ~~2020~~2025, ~~mainly~~which ~~related~~represents tothe ~~payments to suppliers,~~ net ofproceeds ~~receipts~~ from ~~customers~~borrowing.

~~Cash~~Advent’s ~~Flows~~cash ~~used~~flows infrom ~~Investing~~financing activities ~~Activities~~was approximately $0.3 million for the six months ended June 30, 2024, which related to the net cash proceeds from the sale of shares under the Lincoln Park facility.

~~Advent’s cash flows used in investing activities were approximately~~Reverse ~~$(25.6)~~Stock million for the year ended December 31, 2021, which related to the acquisition of fixed assets and the amounts paid for the acquisition of UltraCell LLC on February 18, 2021 and the acquisition of SerEnergy and FES on August 31, 2021, net of cash acquired. Advent expects to invest substantially in fixed assets, plant and equipment in the near future as it executes its product development programs. Advent’s cash flows from investing activities were approximately $(0.1) million for the year ended December 31, 2020, which related to the acquisition of fixed assets.Split

~~Cash~~On April 29, ~~Flows~~2024 ~~from~~and ~~Financing~~April 30, ~~Activities~~2024, our stockholders and Board, respectively, approved a reverse stock split of our Common Stock, at a ratio of 1-for-30 (the “Reverse Stock Split”), as of the Effective Date. The Effective Date of the Reverse Stock Split with the Secretary of the Commonwealth of Massachusetts was 5:00 p.m. on May 13, 2024 and May 14, 2024 in the marketplace.

~~Advent’s~~On the ~~cash~~Effective ~~flows~~Date, ~~from~~the ~~financing~~total ~~activities~~number ~~were~~of ~~approximately $141.5 million~~shares ~~for~~of ~~the~~our ~~year~~Common ~~ended~~Stock ~~December 31,~~held ~~2021,~~by ~~which~~each ~~related~~shareholder towas ~~the~~converted ~~cash~~automatically ~~amount~~into ~~contributed~~the atnumber of ~~the~~whole ~~date~~shares of ~~the~~Common ~~Merger~~Stock ~~(February 4,~~equal ~~2021~~to (i) ~~and~~the ~~proceeds~~number ~~from~~of ~~issuance~~issued and outstanding shares of ~~common~~Common ~~stock~~Stock ~~and~~held ~~additional~~by ~~paid-in~~such ~~capital~~shareholder ~~from~~immediately prior ~~warrants~~to ~~exercise~~the Reverse Stock Split, divided by (ii) 30.

~~Advent’s~~No fractional ~~cash~~shares ~~flows~~were ~~from~~issued ~~financing~~in ~~activities~~connection ~~were~~with ~~approximately $0.9 million for~~ the ~~year~~Reverse ~~ended~~Stock ~~December 31~~Split, ~~2020,~~and ~~which~~stockholders ~~related~~who towould ~~proceeds~~otherwise ofbe ~~issuance~~entitled ofto ~~preferred~~a ~~stock~~fractional share ~~and~~received ~~repayment~~a ofproportional ~~loan~~cash payment in April 2024.

The Company is authorized to issue 501,000,000 shares of Common Stock and that number did not change as a result of the Reverse Stock Split.

The Reverse Stock Split did not have any effect on the stated par value of our Common Stock. The rights and privileges of the holders of shares of Common Stock are unaffected by the Reverse Stock Split. All of our options, warrants and convertible securities outstanding immediately prior to the Reverse Stock Split have been appropriately adjusted by dividing the number of shares of Common Stock into which the options, warrants and convertible securities are exercisable or convertible by 30.

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Contract Assets and Contract Liabilities

Contract assets reflect revenue recognized and performance ~~obligations~~ obligations satisfied in advance of customer billing. As of ~~December~~June 3130, ~~2021,~~2025 and ~~2020~~December 31, 2024, Advent recognized contract assets of $~~1,617,231~~0.6 million and $850.6 million,~~930,~~ respectively, on the consolidated balance sheets. ~~The balance as of December 31, 2021 includes an amount of $587,267 from the SerEnergy and FES acquisition.~~

Advent recognizes contract liabilities when we receive customer payments or have the unconditional right to receive consideration in advance of the performance obligations being satisfied on our contracts. We receive payments from customers based on the terms established in our contracts. Contract liabilities are classified as either current or long-term liabilities in the consolidated balance sheets based on the timing of when we expect to recognize the related revenue. As of ~~December~~June 3130, ~~2021,~~2025 and ~~2020~~December 31, 2024, Advent recognized contract liabilities of $~~1,118,130~~3.7 million and $~~167,761,~~3.2 million, respectively, in the consolidated balance sheets. During the year ended December 31, 2021, the Company recognized the whole amount of $167,761 in revenues. The balance as of December 31, 2021 amounting to $1,118,130 was from the SerEnergy and FES acquisition.

Off-Balance Sheet Commitments and Arrangements

Since the date of our incorporation, Advent has not engaged in any off-balance sheet arrangements, as defined in the rules and regulations of the SEC.

Critical Accounting Policies and Estimates

Advent’s consolidated financial statements have been prepared in accordance with U.S. GAAP. The preparation of these financial statements requires Advent to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the balance sheet date, as well as the reported expenses incurred during the reporting period. Management bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ from those estimates, and such differences could be material to Advent’s financial statements.

Emerging Growth Company Status

Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act)

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are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such an election to opt out is irrevocable. Advent elected not to opt out of such extended transition period which means that when a standard is issued or revised and it has different application dates for public or private companies, Advent, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard, until such time Advent is no longer considered to be an emerging growth company. At times, Advent may elect to early adopt a new or revised standard. See Note 2 in the consolidated financial statements included elsewhere in this prospectus for more information about the recent accounting pronouncements adopted and the recent accounting pronouncements not yet adopted for the years ended December 31, 2021 and 2020.

In addition, Advent intends to rely on the other exemptions and reduced reporting requirements provided by the JOBS Act. Subject to certain conditions set forth in the JOBS Act, if, as an emerging growth company, Advent intends to rely on such exemptions, Advent is not required to, among other things: (a) provide an auditor’s attestation report on Advent’s system of internal control over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act; (b) provide all of the compensation disclosure that may be required of non-emerging growth public companies under the Dodd-Frank Wall Street Reform and Consumer Protection Act; (c) comply with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor’s report providing additional information about the audit and the financial statements (auditor discussion and analysis); and (d) disclose certain executive compensation-related items such as the correlation between executive compensation and performance and comparisons of the Chief Executive Officer’s compensation to median employee compensation.

Advent will remain an emerging growth company under the JOBS Act until the earliest of (a) the last day of Advent’s first fiscal year following the fifth anniversary of the date of the first sale of common equity securities pursuant to an effective registration statement under the Securities Act of 1933, as amended, (b) the last date of Advent’s fiscal year in which Advent has total annual gross revenue of at least $1.1 billion, (c) the date on which Advent is deemed to be a “large accelerated filer” under the rules of the SEC with at least $700.0 million of outstanding securities held by non-affiliates or (d) the date on which Advent has issued more than $1.0 billion in non-convertible debt securities during the previous three years.

While Advent’s significant accounting policies are described in the notes to Advent’s financial statements (see Note 2 in the consolidated financial statements), Advent believes that the following accounting policies require a greater degree of judgment and complexity. Accordingly, these are the policies Advent believes are the most critical to aid in fully understanding and evaluating Advent’s financial condition and results of operations.

Revenue Recognition from January 1, 2019

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), as amended, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. We adopted ASU No. 2014-09 on January 1, 2019, using the modified retrospective approach to all contracts not completed at the date of initial application. ~~The prior period comparative information has not been restated and continues to be reported under the accounting guidance in effect for that period.~~

In accordance with ASC 606, revenue is recognized when control of the promised goods or services are transferred to a customer in an amount that reflects the consideration that ~~the~~Advent ~~Company~~ expects to receive in exchange for those services. We apply the following five steps in order to determine the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its arrangements:

•● identify the contract with a customer,

•● identify the performance obligations in the contract,

•● determine the transaction price,

•● allocate the transaction price to performance obligations in the contract, and

•● recognize revenue as the performance obligation is satisfied.

With significant and recurring customers, we negotiate written master agreements as framework agreements (general terms and conditions of trading), following individual purchase orders. For customers with no master 60

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~~TABLE~~With significant OFand ~~CONTENTS~~recurring customers, we negotiate written master agreements as framework agreements (general terms and conditions of trading), following individual purchase orders. For customers with no master agreements, the approved purchase orders form the contract. Effectively, contracts under the revenue standard have been assessed to be the purchase orders agreed with customers.

agreements, the approved purchase orders form the contract. Effectively, contracts under the revenue standard have been assessed to be the purchase orders agreed with customers.

We have assessed that each product sold is a single performance obligation because the promised goods are distinct on their own and within the context of the contract. In cases where the agreement includes customization services for the contracted products, we are providing integrated services; therefore, the goods are not separately identifiable, but are inputs to produce and deliver a combined output and form a single performance obligation within the context of the contract. Furthermore, we assessed whether it acts as a principal or agent in each of its revenue arrangements and has concluded that in all sales transactions it acts as a principal. Additionally, we, taking into consideration the guidance and indicative factors provided by ASC 606, concluded that it provides assurance type warranties (warranty period is up to two years) as it does not provide a service to the customer beyond fixing defects that existed at the time of sale. We, based on historical performance, current circumstances, and projections of trends, estimated that no allowance for returns as per warranty policy should be recognized, at the time of sale, accounted for under ASC 460, Guarantees.

Under ASC 606, we estimate the transaction price, including variable consideration, at the commencement of the contract and recognize revenue over the contract term, rather than when fees become fixed or determinable. In other words, where contracts with customers include variable consideration (i.e. volume rebates), we estimate at contract inception the variable consideration and adjust the transaction price only to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. Furthermore, no material rights or significant financing components have been identified in our contracts. Payment terms generally include advance payment requirements. The time between a customer’s payment and completion of the performance obligation is less than one year. Payment terms are in the majority fixed and do not include variable consideration, except from volume rebates.

Revenue from satisfaction of performance obligations is recognized based on identified transaction price. The transaction price reflects the amount to which we have rights under the present contract. It is allocated to the distinct performance obligations based on standalone selling prices of the services promised in the contract. In cases of more than one performance obligation, we allocate transaction price to the distinct performance obligations in proportion to their observable stand-alone selling prices and recognize revenue as those performance obligations are satisfied.

In the majority of cases of product sales, revenue is recognized at a point in time when the customer obtains control of the respective goods that is, when the products are shipped from our facilities as control passes to the customer in accordance with agreed contracts and the stated shipping terms. In cases where the contract includes customization services, in which one performance obligation is identified, revenue is recognized over time as our performance does not create an asset with alternative use and we have an enforceable right to payment for performance completed to date. We use the input method (i.e., cost-to-cost method) to measure progress towards complete satisfaction of the performance obligation.

Income from grants and related deferred income

Grants include cash subsidies received from various institutions and organizations. Grants are recognized as other income. Such amounts are recognized in the consolidated statements of operations when all conditions attached to the grants are fulfilled.

Condition to the grants would not be fulfilled unless related costs have been characterized as eligible by the grantors, are actually incurred and there is certainty that costs are allowable. These grants are recognized as deferred income when received and recorded in income when the eligible and allowable related costs and expenses are incurred. Under all grant programs, a coordinator is specified. The coordinator, among other, receives the funding from the grantor and proceeds to its distribution to the parties agreed in the process specified in the program. We assessed whether it acts as a principal or agent in its role as a coordinator for specific grants and has concluded that in all related transactions it acts as an agent.

~~Goodwill~~61

~~The~~Table ~~Company allocates the fair value~~ of purchase consideration transferred in a business acquisition to the tangible assets acquired, liabilities assumed, and intangible assets acquired based on their estimated fair values. The excess of the fair value of purchase consideration transferred over the fair values of these identifiable assets and Contents

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liabilities is recorded as goodwill. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. Significant estimates in valuing certain intangible assets include, but are not limited to, future expected cash flows from acquired licenses, trade names, in process research and development (“R&D”), useful lives and discount rates, patents, customer clientele, customer contracts and know-how. Management's estimates of fair value are based upon assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. During the measurement period, the Company may record adjustments to the assets acquired and liabilities assumed, with the corresponding offset to goodwill. Upon the conclusion of the measurement period, any subsequent adjustments are recorded in the consolidated statement of operations.

For significant acquisitions, the Company obtains independent appraisals and valuations of the intangible (and certain tangible) assets acquired and certain assumed obligations as well as equity. The Company analyzes each acquisition individually and all acquisitions within each reporting period in aggregate to determine if those are material acquisitions in the context of ASC 805-10-50.

The estimated fair values and useful lives of identified intangible assets are based on many factors, including estimates and assumptions of future operating performance and cash flows of the acquired business, estimates of cost avoidance, the nature of the business acquired, the specific characteristics of the identified intangible assets and our historical experience and that of the acquired business. The estimates and assumptions used to determine the fair values and useful lives of identified intangible assets could change due to numerous factors, including product demand, market conditions, regulations affecting the business model of our operations, technological developments, economic conditions and competition.

We conduct a goodwill impairment analysis annually in the fourth fiscal quarter, or more frequently, if changes in facts and circumstances indicate that the fair value of our reporting units may be less than their carrying amounts. In testing goodwill for impairment, the Company first assesses qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then additional impairment testing is not required. When the Company determines a fair value test is necessary, it estimates the fair value of a reporting unit and compares the result with its carrying amount, including goodwill. If the carrying amount of a reporting unit exceeds its fair value, an impairment is recorded equal to the amount by which the carrying value exceeds the fair value, up to the amount of goodwill associated with the reporting unit. Currently, we identify one reporting unit.

Income Taxes

Advent follows the asset and liability method of accounting for income taxes under ASC 740, Income Taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to temporary differences between the financial statements carrying amounts of existing assets and liabilities and their respective tax bases. This method also requires the recognition of future tax benefits, such as net operating loss carry forwards, to the extent that it is more likely than not that such benefits will be realized. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. Valuation allowances are reassessed periodically to determine whether it is more likely than not that the tax benefits will be realized in the future and if any existing valuation allowance should be released.

Part of the Advent’s business activities are conducted through its subsidiaries outside of U.S. Earnings from these subsidiaries are generally indefinitely reinvested in the local businesses. Further, local laws and regulations may also restrict certain subsidiaries from paying dividends to their parents. Consequently, Advent generally does not accrue income taxes for the repatriation of such earnings in accordance with ASC 740, “Income Taxes.” To the extent that there are excess accumulated earnings that we intend to repatriate from any such subsidiaries, we recognize deferred tax liabilities on such foreign earnings.

Advent assesses its income tax positions and records tax benefits for all years subject to examination based on the evaluation of the facts, circumstances, and information available at each reporting date. For those tax positions with a greater than 50 percent likelihood of being realized upon ultimate settlement with a taxing authority that has full knowledge of all relevant information, Advent records a tax benefit. For those income tax positions that are not likely to be sustained, no tax benefit is recognized in the consolidated financial statements. Advent recognizes interest and penalties related to uncertain tax positions as part of the provision for income taxes.

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full knowledge of all relevant information, Advent records a tax benefit. For those income tax positions that are not likely to be sustained, no tax benefit is recognized in the consolidated financial statements. Advent recognizes interest and penalties related to uncertain tax positions as part of the provision for income taxes.

ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities. For those income tax positions that are not likely to be sustained, no tax benefit is recognized in the consolidated financial statements. Advent recognizes interest and penalties related to uncertain tax positions as part of the provision for income taxes.

For the ~~years~~six months ended ~~December~~June 3130, ~~2021~~2025 and ~~2020~~2024, net income tax ~~benefits~~ (~~provisions~~expenses) benefits of $~~922,510~~(1) thousand and $0.1 million, respectively, have been recorded in the consolidated statements of operations. Advent is currently not aware of any issues under review that could result in significant accruals or material deviation from its position. ~~The~~Advent ~~Company~~ is subject to income tax examinations by major taxing authorities.

~~The Company~~ Advent and its U.S. subsidiaries may be subject to potential examination by U.S. federal, state and city, while ~~the Company~~Advent’s subsidiaries outside U.S. may be subject to potential examination by their taxing authorities in the areas of income taxes. These potential examinations may include questioning the timing and amount of deductions, the nexus of income among various tax jurisdictions and compliance with the U.S. federal, state and city, and tax laws in the countries where business activities of ~~Company~~Advent’s subsidiaries are conducted. On On December 22, 2017, the Tax Cuts and Jobs Act of 2017 ~~(“Tax Reform”)~~ was signed into legislation. As part of the legislation, the U.S. corporate income tax rate was reduced from 35% to 21%, among other changes.

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Warrant Liability

~~The Company~~ Advent accounts for the 26878,~~369,557~~985 warrants (comprising of 22 813,~~029,279~~314 Public Warrants and 365,~~940,278~~ 671 Private Placement Warrants) issued in connection with the initial public offering and the ~~400~~13,~~000~~ 333 Working Capital Warrants issued at the consummation of the Business Combination in accordance with ASC 815-40-15-7D. If the warrants do not meet the criteria for equity treatment, they must be recorded as liabilities. We have determined that only the Private Placement Warrants and Working Capital Warrants must be recorded as liabilities and accordingly, ~~the~~we ~~Company~~classify ~~classifies~~ these warrant instruments as liabilities at their fair value and adjusts the instruments to fair value at each reporting period. These liabilities are subject to re-measurement at each balance sheet date until exercised, and any change in fair value is recognized in ~~the~~our ~~Company's~~ statement of operations. The fair value of the Private Placement Warrants and the Working Capital Warrants has been determined using either the quoted price, if available, or was based on a modified Black-Scholes-Merton model. The fair value of the Private Placement Warrants and the Working Capital Warrants has been determined based on a modified Black-Scholes-Merton model for the ~~year~~six months ended ~~December~~June 3130, ~~2021~~2025 and 2024.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by Advent as of the specified effective date. Unless otherwise discussed, Advent believes that the impact of recently issued standards that are not yet effective will not have a material impact on Advent’s financial position or results of operations under adoption.

See Note 2 in the condensed consolidated financial statements included elsewhere in this ~~prospectus~~report for more information about recent accounting pronouncements, the timing of their adoption and Advent’s assessment, to the extent Advent has made one, of their potential impact on Advent’s financial condition and results of operations.

Supplemental Non-GAAP Measures and Reconciliations

In addition to providing measures prepared in accordance with GAAP, we present certain supplemental non-GAAP measures. These measures are EBITDA, Adjusted EBITDA and Adjusted Net Income / (Loss), which we use to evaluate our operating performance, for business planning purposes and to measure our performance relative to that of our peers. These non-GAAP measures do not have any standardized meaning prescribed by GAAP and therefore may differ from similar measures presented by other companies and may not be comparable to other similarly titled measures. We believe these measures are useful in evaluating the operating performance of ~~the Company~~Advent’s ongoing business. These measures should be considered in addition to, and not as a substitute for net income, operating expense and income, cash flows and other measures of financial performance and liquidity reported in accordance with GAAP. The calculation of these non-GAAP measures has been made on a consistent basis for all periods presented.

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EBITDA and Adjusted EBITDA

These supplemental non-GAAP measures are provided to assist readers in determining our operating performance. We believe this measure is useful in assessing performance and highlighting trends on an overall basis. We also believe EBITDA and Adjusted EBITDA are frequently used by securities analysts and investors when comparing our results with those of other companies. EBITDA differs from the most comparable GAAP measure, net income / (loss), primarily because it does not include interest, income taxes, depreciation of property, plant and equipment, and amortization of intangible assets. Adjusted EBITDA adjusts EBITDA for ~~transactional~~items ~~gains~~such ~~and~~as ~~losses~~one-time transaction costs, asset impairment charges, ~~finance~~ and ~~other~~fair ~~income~~value ~~and~~changes ~~acquisition~~in ~~costs~~the warrant liability.

The following tables show a reconciliation of net income / (loss) to EBITDA and Adjusted EBITDA for the three months ended December 31, 2021 and 2020 and for the years ended December 31, 2021 and 2020.63

EBITDA and Adjusted EBITDA	Three months ended December 31, (Unaudited)			Years Ended December 31,
(in Millions of US dollars)	2021	2020	$ change	2021	2020	$ change
Net loss	$(9.00)	$(1.70)	(7.30)	$(20.52)	$(3.12)	(17.40)
Depreciation of property and equipment	$0.38	$0.00	0.38	$0.56	$0.02	0.54
Amortization of intangibles	$0.71	$0.00	0.71	$1.18	$0.00	1.18
Finance (income) costs, net	$0.02	$0.01	0.01	$0.05	$0.01	0.04
Other (income) expenses, net	$0.06	$0.04	0.02	$(0.02)	$0.02	(0.04)
Foreign exchange differences, net	$0.04	$0.00	0.04	$0.04	$0.03	0.01
Income tax	$(0.87)	$0.00	(0.87)	$(0.92)	$0.00	(0.92)
EBITDA	$(8.66)	$(1.65)	(7.01)	$(19.63)	$(3.04)	(16.59)
Net change in warrant liability	$(6.91)	$0.00	(6.91)	$(22.74)	$0.00	(22.74)
One-Time Transaction Related Expenses(1)	$0.00	$0.00	0.00	$5.87	$0.00	5.87
One-Time Transaction Related Expenses(2)	$0.00	$0.00	0.00	$0.89	$0.00	0.89
Executive severance(3)	$0.00	$0.00	0.00	$2.44	$0.00	2.44
Adjusted EBITDA	$(15.57)	$(1.65)	(13.92)	$(33.17)	$(3.04)	(30.13)

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~~(1)~~The following ~~Bonus~~tables ~~awarded~~show ~~after~~a ~~consummation~~reconciliation of ~~the~~net ~~Business~~loss ~~Combination~~to ~~effective~~EBITDA ~~February~~and 4Adjusted EBITDA for the three months ended June 30, ~~2021~~2025 and 2024.

(2) Transaction costs related to the acquisition of SerEnergy/FES.

EBITDA and Adjusted EBITDA	Three months ended June 30, (Unaudited)									Six months ended June 30, (Unaudited)
(in Millions of US dollars)	2025			2024			$ change			2025			2024			$ change
Net loss from continuing operations	$	(3.80	)	$	(10.21	)		6.41		$	(7.07	)	$	(19.63	)		12.56
Depreciation of property and equipment	$	0.20		$	-			0.20		$	0.39		$	0.69			(0.30	)
Amortization of intangibles	$	-		$	-			-		$	0.01		$	-			0.01
Finance income / (expenses), net	$	0.33		$	0.06			0.27		$	0.57		$	0.29			0.28
Loss contingency	$	0.84		$	(0.04	)		0.88		$	1.03		$	4.87			(3.84	)
Net gains / (losses) on disposal/write-off property, plant and equipment and intangible assets	$	-		$	12.72			(12.72	)	$	-		$	12.74			(12.74	)
Other income / (expenses), net	$	-		$	(0.01	)		0.01		$	-		$	(0.01	)		0.01
Foreign exchange differences, net	$	(0.29	)	$	0.16			(0.45	)	$	(0.39	)	$	0.17			(0.56	)
Income taxes	$	-		$	-			-		$	-		$	(0.06	)		0.06
EBITDA	$	(2.72	)	$	2.68			(5.40	)	$	(5.46	)	$	(0.94	)		(4.52	)
Net change in warrant liability	$	-		$	-			-		$	-		$	(0.06	)		0.06
Adjusted EBITDA	$	(2.72	)	$	2.68			(5.40	)	$	(5.46	)	$	(1.00	)		(4.46	)

~~(3)~~Adjusted Net ~~Former~~Loss ~~Financial~~from ~~Officer~~continuing ~~resignation.~~operations

This supplemental non-GAAP measure is provided to assist readers in determining our financial performance. We believe this measure is useful in assessing our actual performance by adjusting our results from continuing operations for changes in warrant liability and one-time transaction costs. Adjusted Net ~~Income~~Loss from continuing operations differs from the most comparable GAAP measure, net loss, primarily because it does not include one-time transaction costs, asset impairment charges and warrant liability changes. The following table shows a reconciliation of net income/(~~Loss~~loss) for three months ended June 30, 2025 and 2024.

This supplemental non-GAAP measure is provided to assist readers in determining our financial performance. We believe this measure is useful in assessing our actual performance by adjusting our results from continuing operations for changes in warrant liability and one-time transaction costs. Adjusted Net Loss differs from the most comparable GAAP measure, net income / (loss), primarily because it does not include one-time transaction costs and warrant liability changes. The following table shows a reconciliation of net income/(loss) for three months ended December 31, 2021 and 2020 and for the years ended December 31, 2021 and 2020.

Adjusted Net Loss	Three months ended June 30, (Unaudited)								Six months ended June 30, (Unaudited)
(in Millions of US dollars)	2025			2024			$ change		2025			2024			$ change
Net loss	$	(3.80	)	$	(10.21	)		6.41	$	(7.07	)	$	(19.63	)		12.56
Net change in warrant liability	$	-		$	-			-	$	-		$	(0.06	)		0.06
Adjusted Net Loss	$	(3.80	)	$	(10.21	)		6.41	$	(7.07	)	$	(19.69	)		12.62

Adjusted Net Loss	Three months ended December 31, (Unaudited)			Years Ended December 31,
(in Millions of US dollars)	2021	2020	$ change	2021	2020	$ change
Net loss	$(9.00)	$(1.70)	(7.30)	$(20.52)	$(3.12)	(17.40)
Net change in warrant liability	$(6.91)	$0.00	(6.91)	$(22.74)	$0.00	(22.74)
One-Time Transaction Related Expenses(1)	$0.00	$0.00	0.00	$5.87	$0.00	5.87
One-Time Transaction Related Expenses(2)	$0.00	$0.00	0.00	$0.89	$0.00	0.89
Executive severance(3)	$0.00	$0.00	0.00	$2.44	$0.00	2.44
Adjusted Net Loss	$(15.91)	$(1.70)	(14.21)	$(34.06)	$(3.12)	(30.94)

~~(1)~~Table ~~Bonus awarded after consummation~~ of ~~the Business Combination effective February 4, 2021.~~Contents

~~(2)~~Item 3. ~~Transaction~~Quantitative ~~costs~~and ~~related~~Qualitative toDisclosures ~~the~~About ~~acquisition~~Market ~~of SerEnergy/FES~~Risk.

~~(3)~~Advent is ~~Former~~exposed ~~Financial~~to ~~Officer~~a ~~resignation~~variety of market and other risks, including the effects of changes in interest rates and inflation, as well as risks to the availability of funding sources, hazard events and specific asset risks.

49Interest Rate Risk

~~TABLE~~Advent holds OFcash ~~CONTENTS~~and cash equivalents for working capital, investment and general corporate purposes. As of June 30, 2025, Advent had an unrestricted cash balance of approximately $0.1 million, consisting of operating and savings accounts which are not affected by changes in the general level of U.S. interest rates. Advent has short-term debt of $1.5 million.

Inflation Risk

Advent does not believe that inflation currently has a material effect on its business. To mitigate cost increases caused by inflation, Advent has taken steps such as searching for alternative supplies at a lower cost and pre-buying materials and supplies at a more advantageous price in advance of its intended use.

Foreign Exchange Risk

Advent has costs and revenues denominated in Euros, and therefore is exposed to fluctuations in exchange rates. To date, Advent has not entered into any hedging transactions to mitigate the effect of foreign exchange due to the relatively low exposure. As we increase in scale, we expect to continue to realize a portion of our revenues and costs in foreign currencies, and therefore expect to put in place appropriate foreign exchange risk mitigation features in due course.

Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer (currently also serving as Interim Chief Financial Officer) has evaluated the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act), as of the end of the period covered by this Report on Form 10-Q.

The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized, and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.

Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and our management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

As described below, based on the evaluation of our disclosure controls and procedures as of the end of the period covered by this Report on Form 10-Q, management identified material weaknesses in our internal control over financial reporting. As a result of the material weaknesses, our Chief Executive Officer (currently also serving as Interim Chief Financial Officer) has concluded that, as of June 30, 2025, our disclosure controls and procedures were not effective to provide reasonable assurance that information required to be disclosed in the reports we file and submit under the Exchange Act is recorded, processed, summarized, and reported as and when required.

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Notwithstanding this material weaknesses identified, our management, including our Chief Executive Officer (currently also serving as Interim Chief Financial Officer), has concluded that our financial statements included in this Report on Form 10-Q present fairly, in all material respects, our financial position, results of operations, and cash flows for the periods presented in accordance with U.S. GAAP.

Management’s Quarterly Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rule 13a-15(f) or 15d-15(f) of the Exchange Act. Internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with U.S. GAAP, and includes those policies and procedures that:

(i)

pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of our assets;

(ii)

provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S. GAAP, and that our receipts and expenditures are being made only in accordance with authorizations of our management and directors; and

(iii)

provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of our assets that could have a material effect on our financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect all misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Our management assessed the effectiveness of our internal control over financial reporting as of June 30, 2025, using the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control-Integrated Framework (2013).

Based on this assessment and the evaluation of those criteria, management, including our Chief Executive Officer (currently also serving as Interim Chief Financial Officer), concluded that our internal control over financial reporting was not effective as of June 30, 2025, due to the material weaknesses described below.

A material weakness (as defined in Rule 12b-2 under the Exchange Act) is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of a company’s annual or interim financial statements will not be prevented or detected on a timely basis.

Entity-Level Control Environment

The entity-level control environment did not adequately support the prevention, detection or correction of material misstatements. We identified deficiencies in all five components of the entity-level control environment, including the control environment, control activities, information and communication, monitoring and risk assessment that aggregated into material weaknesses. Overall, we did not sufficiently establish internal control policies and procedures in our material business processes related to the financial reporting process.

Financial Statement Close and Reporting Process

We did not adequately design and execute controls that addressed the relevant financial statement assertions over the close and reporting process including review controls, journal entries and adjustments during the period-end reporting, changes to general ledger master data. We lacked in certain instances sufficient and appropriate documentation, reconciliation controls and segregation of duties controls.

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IT Processes

Internal controls that address the IT risks of applications were not adequately designed and implemented. Management did not adequately perform controls or retain sufficient and appropriate evidence over 1) user access controls 2) application change controls and 3) the timeliness of segregation of duties access monitoring procedures.

To mitigate the potential impact of material weaknesses, and prior to filing this report, we performed additional analysis and other post-closing procedures to determine that our consolidated financial statements are prepared in accordance with U.S. GAAP. These material weaknesses did not result in any material misstatements and there were no changes to previously released financial statements. Notwithstanding our material weaknesses, we have concluded that the financial statements and other financial information included in this prospectus fairly present in all material respects our financial position, results of operations, and cash flows for the periods presented in conformity with U.S. GAAP.

Remediation Plan

Following the identification of the material weaknesses in our internal control over financial reporting as of June 30, 2025, and with the oversight of the Audit Committee of our Board of Directors, we will commence remediation efforts to enhance our control environment.

●

Hiring and augmenting our team with knowledgeable and qualified IT, accounting, and finance professionals.

●

Enhancing the robustness and effectiveness of our IT systems and control environment.

●

Enhancing related policies and process documentation, implementing new controls or redesigning existing ones, and improving the skills of process owners.

●

Training process owners, evaluating the adoption of revised policies and procedures, and monitoring results.

●

Increasing the frequency and independence of testing the design and operating effectiveness of controls.

Management is committed to successfully implementing the remediation plan as promptly as possible. Our plan can only be accomplished over time, and we can offer no assurance that these initiatives will ultimately have the intended effects. See “Risk Factors—Risks Related to Our Operations and Business — We have identified material weaknesses in our system of internal controls pursuant to Section 404 of the Sarbanes-Oxley Act of 2002. If not remediated, these material weaknesses could result in material misstatements in our consolidated financial statements. We may be unable to develop, implement and maintain appropriate controls in future periods.” within our 2024 10-K.

Changes in Internal Control over Financial Reporting

Financial Statement Close and Reporting Process

We did not adequately maintain accounting records at the consolidated level, resulting in a loss of access to underlying systems and records with the bankruptcy of Advent Technologies A/S in July 2024. The Company generated estimates using internal management reporting and bank statements as part of the September 30, 2024, close and reporting process.

Except as otherwise noted above and also under “Remediation Plan,” including the on-going remediation efforts described, there were no other changes in our internal control over financial reporting (as such term is defined in Exchange Act Rule 13a–15(f) and 15d-15(f)) during the quarter ended June 30, 2025, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting. Our plans for remediating the material weaknesses, described above, will constitute changes in our internal control over financial reporting, prospectively, when such remediation plans are effectively implemented.

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BUSINESS

The following discussion reflects the business of Advent. References to “Advent”, the “Company”, “us”, “we”, “our” and any related terms prior to the closing of the Business Combination are intended to mean Advent Technologies Inc., a Delaware corporation, and its consolidated subsidiaries and after the closing of the Business Combination are intended to mean Advent Technologies Holdings, Inc., a Delaware corporation, and its consolidated subsidiaries.

Overview

We are an advanced materials and technology development company operating in the fuel cell and hydrogen technology space, including liquid hydrogen carriers such as methanol. We ~~develop~~are a world-leading company in the development of HT-PEM (High Temperature Proton Exchange Membrane) technology (with approximately 150 patents issued, ~~manufacture~~pending, ~~and~~or ~~assemble~~licensed ~~complete~~worldwide). The HT-PEM fuel cell technology enables off-grid power systems to produce clean power from various green fuels (hydrogen, methanol, bio and e-Methanol, and renewable natural gas) and to function with higher efficiency at extreme ambient temperatures and in general extreme environmental conditions (humidity, air pollution). Advent’s main operations focus on developing and manufacturing the ~~critical~~Membrane ~~components~~Electrode ~~that~~Assembly ~~determine~~(MEA) and the ~~performance~~fuel cell stack, which is the core electrochemical element and the most critical component of ~~hydrogen~~the fuel ~~cells~~cell. The MEA and ~~other~~the ~~energy~~fuel cell stack largely determines lifetime, power density, efficiency, and overall cost of installation and operation for all applications. Advent is working with global market-leading OEMs with the goal of bringing to the market complete fuel cell systems for a range of applications in the stationary power markets (backup, off-grid, and portable power) and the heavy-duty mobility markets (automotive, aviation, marine).

~~We develop and manufacture high-temperature proton exchange~~Our ~~membranes~~mission ~~(“HT-PEM”~~is orto ~~“HT-PEMs”)~~bring ~~and~~ fuel ~~cell~~cells ~~systems~~that ~~for~~have ~~the~~a ~~off-grid~~lower ~~and~~Total ~~portable~~Cost ~~power~~of ~~markets~~Ownership ~~and~~(TCO) ~~plan~~ to ~~expand into the mobility~~ market. ~~Select~~when ~~applications~~compared ~~are~~to ~~telecom~~diesel ~~towers~~generators ~~(5G~~ and ~~older), energy infrastructure (methane emissions~~internal ~~mitigation~~combustion ~~for the oil and gas industry), and portable power for defense or emergency response units~~engines. Our ~~mission~~goal is to become a leading provider of HT-PEM fuel cell systems, ~~HT-PEMs,~~stacks ~~fuel cells,~~ and HT-PEM -based membrane electrode assemblies (“MEA” or “MEAs”)~~, which are critical components used in fuel cells, and other electrochemical applications such as electrolyzers and flow batteries~~. We develop the core chemistry components, the MEAs, that enable fuel cells to operate at high temperatures and also provide these MEAs to third-party fuel cell manufacturers. HT-PEM fuel cells have the advantage of operating with multiple low-carbon fuels (in addition to hydrogen) and under extreme conditions.

~~Our~~A large portion of our current revenue is derived from Joint Development Agreements (JDAs) and Technology Assessment Agreements (TAAs) with world-leading OEMs for the ~~sale~~development of joint products. The ultimate goal is for OEMs to bring fuel cell systems specialized for ~~and~~each ~~from~~application to the ~~sale~~market. ofThese ~~MEAs,~~systems ~~membranes,~~will be branded by the OEMs and ~~electrodes~~function ~~for~~with ~~specific~~Advent-inside ~~applications~~technology (the Advent MEA and/or the Advent fuel cell stack). The Company also has extensive know-how and IP in the development of complete fuel cell systems that it intends to license out to OEMs and ~~energy~~Tier ~~storage~~1s ~~(flow~~through ~~battery)~~technology ~~markets~~license agreements. While fuel cell ~~systems~~stack sales and associated revenue is expected to provide the majority of our income in the near future, the MEA innovation is expected to facilitate future strategic partnerships between ~~us and~~ Tier 1 suppliers and us and original equipment manufacturers (“OEMs”) as these downstream manufacturers develop their own white-~~labelled~~labeled HT-PEM products. We have had early success in forging such strategic partnerships, as with the case of Airbus for the aerospace sector and previously with Siemens Energy for the maritime industry. The US Army development contracts for human portable power fuel cells also fall under this category.

~~We have our~~ Our headquarters are in ~~Boston~~Livermore, ~~Massachusetts~~California, and ~~are~~we ~~building out~~have aMEA ~~product~~and ~~development~~fuel ~~and~~cell ~~research~~stack ~~and~~product development ~~facility~~facilities in ~~Charlestown~~Livermore, ~~Massachusetts~~California and ~~expected~~Patras, toGreece. ~~open~~Our ininvestment ~~2022,~~priorities ~~and~~are ~~have~~increasing MEA ~~fabrication~~performance and ~~system~~meeting ~~production~~the ~~facilities~~milestones inof ~~Livermore,~~the ~~California;~~Joint ~~Achern,~~Development ~~Germany; Aalborg, Denmark; and~~Agreements ~~Patras,~~we ~~Greece.~~have Wewith ~~plan~~various tocustomers ~~scale-up U.S.~~ and ~~European~~partners ~~production~~including ~~and~~Airbus, ~~its~~Hyundai ~~global~~Motors ~~sales~~and ~~operations~~the toUS ~~handle future demand~~Army. Our ~~investment~~business priorities are ~~increasing~~to ~~MEA~~expand ~~production~~our network ~~volumes,~~of ~~executing~~strategic onOEM ~~new~~relationships ~~product~~in ~~development~~the ~~initiatives (next-generation~~Automotive ~~fuel cell systems~~ and ~~MEAs),~~large-scale ~~and~~Stationary ~~optimizing~~power ~~production operations to improve unit costs~~markets.

Our ~~principal focus is on the total fuel cell market, from~~ components to complete systems, and we plan to use our products and technology to address pressing global climate needs. Fuel cell and hydrogen technology is expected to play a critical role in global decarbonization. In order to meet the targets established in the Paris Climate Accords, which seek to mitigate climate change and maintain global temperature less than 1.5°C-2.0°C above pre-industrial levels, the global community will need to accelerate the adoption of technologies like our fuel cells, that reduce or eliminate emissions of carbon dioxide and other greenhouse gases. We believe that fuel cells will be a key component of the future energy generation platform given that:Background

•Advent Technologies ~~Fuel~~Holdings, ~~cells~~Inc., ~~generate~~a ~~electricity~~Delaware ~~and~~corporation ~~heat~~(the ~~from~~“Company”), ~~hydrogen-based~~was ~~fuels,~~originally ~~thereby~~named ~~substantially~~AMCI ~~reducing~~Acquisition ~~emissions~~Corp. of(“AMCI”), and ~~carbon~~was ~~dioxide~~established ~~and~~as ~~other~~a ~~pollutants~~special ~~generated~~purpose byacquisition ~~the~~company, ~~combustion~~which ~~process~~completed its initial public offering in ~~internal~~November 2018. ~~combustion~~AMCI was ~~engines~~incorporated ~~(“ICE”~~for orthe ~~“ICEs”)~~purpose ~~and~~of ~~diesel~~effecting ~~generators.~~a ~~Fuel~~merger, ~~cells~~capital ~~can~~stock beexchange, ~~powered~~asset ~~autonomously~~acquisition, ~~for~~stock ~~hours~~purchase, reorganization or similar ~~days~~business ~~where~~combination ~~the~~with ~~fuel~~one ~~comes~~or ~~from~~more abusinesses, ~~discrete source~~and, orprior ~~for~~to ~~longer~~the ~~where~~Business ~~there~~Combination, isthe Company was a ~~pipeline~~“shell orcompany” as ~~other~~defined ~~large~~under ~~available~~the ~~source~~Securities ofExchange ~~fuel~~Act ~~such~~of 1934, as aamended ~~tank~~(the “Exchange Act”), because it had no operations and nominal assets consisting almost entirely of cash.

• Fuel cells utilize fuels with a high energy density relative to lithium-ion batteries and other battery technology (according to ARPA-E power densities, hydrogen contains 40,000 Wh/kg while lithium-ion batteries carry only about 260Wh/kg). This makes fuel cell technology well-suited for use in mobility and off-grid energy generation applications where battery technology faces limitations such as lifespan, self-discharge, weight (fuel cells are between 3 to 25 times lighter than batteries providing equivalent power), operation under almost any weather conditions, and recharge times.68

•Table ~~We expect that hydrogen will also be used to create liquid, synthetic fuels (eFuels like eMethanol, made by combining hydrogen with carbon dioxide for a net-zero liquid fuel) that have the advantage~~ of lower transportation costs and network infrastructure investment relative to hydrogen gas. Fuels like methanol have become subject to an increasing interest in Asia because they are currently available. We believeContents

50On February 4, 2021, AMCI consummated the previously announced business combination (“Business Combination”) pursuant to the terms of that certain agreement and plan of merger (the “Agreement and Plan of Merger”) dated October 12, 2020, by and among AMCI, AMCI Merger Sub Corp., a Delaware corporation and newly formed wholly-owned subsidiary of AMCI (“Merger Sub”), AMCI Sponsor LLC (the “Sponsor”), solely in the capacity as the representative from and after the effective time of the Business Combination for the stockholders of AMCI, Advent Technologies, Inc., a Delaware corporation (“Legacy Advent”), and Vassilios Gregoriou, solely in his capacity as the representative from and after the effective time for the Legacy Advent stockholders (the “Seller Representative”), as amended by Amendment No. 1 and Amendment No. 2 to the Agreement and Plan of Merger, dated as of October 19, 2020 and December 31, 2020, respectively, by and among AMCI, Merger Sub, Sponsor, Legacy Advent, and Seller Representative. In connection with the closing of the Business Combination (the “Closing”), AMCI acquired 100% of the stock of Legacy Advent (as it existed immediately prior to the Closing) and its subsidiaries.

~~TABLE~~On the OFClosing ~~CONTENTS~~Date, and in connection with the Closing, AMCI changed its name to “Advent Technologies Holdings, Inc.” and each outstanding share of Class A common stock, including any shares of Class B common stock that were converted into shares of Class A common stock, were redesignated as our Common Stock. We continued the listing of our Common Stock and public warrants (or tradeable warrants) on the Nasdaq under the symbols “ADN” and “ADNWW”, respectively. Prior to the Closing, our Class A common stock, public warrants and units were listed on the Nasdaq Stock Market under the symbols “AMCI”, “AMCIW” and “AMCIU”.

~~methanol~~The rights ~~has~~of ~~the~~holders ~~potential~~of toour ~~become~~Common aStock ~~leading~~and ~~zero-emissions~~warrants ~~liquid~~are ~~fuel~~governed ~~that~~by ~~can leverage~~our ~~the~~second ~~current~~amended ~~global~~and ~~infrastructure~~restated ~~from~~certificate ~~gas~~of ~~stations~~incorporation, toour amended ~~fuel tankers~~ and ~~trucks.~~restated ~~Given~~bylaws and the ~~urgency~~Delaware toGeneral ~~decarbonize~~Corporation ~~power~~Law ~~generation~~(the “DGCL”), and ~~the~~in ~~challenges~~ the ~~investment~~case ~~requirement~~of ~~poses~~the ~~for~~warrants, ~~developing~~the ~~countries~~Warrant Agreement, wedated ~~expect~~November 15, ~~methanol~~2018 toby ~~have an~~and ~~increasingly~~between ~~significant~~AMCI ~~role~~and asContinental aStock ~~liquid~~Transfer ~~hydrogen~~& ~~carrier~~Trust ~~and~~Company, aas ~~low/no~~warrant ~~carbon~~agent. ~~dioxide~~See the ~~emission~~section ~~alternative~~entitled to“Description ~~oil~~of Securities”.

~~The Fuel Cell Industry~~RESCUE Project

~~Fuel~~The Company, ~~cell~~through ~~and~~its ~~hydrogen~~wholly-owned ~~technology~~subsidiary, isAdvent ~~expected~~Technologies, toSA, ~~play~~announced aon ~~critical role~~February 11, in2025 ~~global decarbonization given~~ the ~~clean~~launch ~~nature~~ of ~~emissions~~the ~~from~~RESCUE ~~hydrogen~~project, a ~~and~~strategic ~~hydrogen-carrier~~initiative ~~fuels~~funded ~~relative~~under ~~to fossil fuels. In addition,~~ the ~~challenges~~HORIZON-JTI-CLEANH2-2024-04-01 ~~associated~~call ~~with~~for ~~existing~~“Portable ~~battery~~Fuel ~~technology~~Cells ~~limit~~for itBackup ~~from~~Power ~~mass~~During ~~adoption across~~Natural ~~industries.~~Disasters ~~Globally, an average of $38 billion per annum is expected~~ to beSupport ~~invested~~Critical inInfrastructures.” ~~the~~The ~~hydrogen~~four ~~and~~year ~~fuel~~project ~~cell~~has ~~sector~~a ~~between~~total ~~2020~~budget ~~and 2040 with the goal~~ of ~~significantly~~€5 ~~increasing~~million, ~~production~~and ~~capacity~~a ~~while~~funding ~~lowering the cost~~ rate of ~~production~~70%. ~~While~~ ~~the~~Advent’s ~~availability~~approved ofbudget ~~hydrogen~~for ~~limited~~ the ~~fuel~~initiative ~~cell industry in the past, it~~ is ~~now~~€2.16 ~~expected to become an opportunity for growth, particularly in sectors such as industrials, power generation and automotive~~million.

~~Within~~RESCUE aims ~~the~~to ~~fuel~~develop ~~cell~~a ~~market~~certified, ~~our~~portable ~~products~~50 ~~have~~kW ~~significant advantages~~power ~~relative~~generator system designed to ~~its~~deliver ~~competitors~~reliable, ~~that~~sustainable ~~are~~backup ~~focused~~power in critical situations based on ~~low~~HT-~~temperature~~PEM ~~proton~~technology. ~~exchange~~This ~~membrane~~collaborative ~~technology~~effort ~~(“LT-PEM”~~brings ortogether ~~“LT~~world-~~PEMs”~~class partners, led by DLR (Germany). Weas ~~believe~~the ~~these~~project coordinator, ~~advantages~~with ~~will~~participation ~~help~~from usAdvent ~~secure~~Technologies ~~commercial~~(Greece), ~~opportunities~~CERTH in(Greece), ~~the~~THW ~~fuel~~(Germany), ~~cell~~DTU ~~market~~(Denmark), and ~~help~~ProACT (Greece). ~~drive~~The ~~wide~~RESCUE project responds to the critical need for sustainable, portable power solutions, particularly in disaster-~~spread~~stricken ~~adoption~~regions where ofsupporting ~~fuel~~essential ~~cell~~infrastructure ~~technology~~is paramount. ~~The~~By ~~benefits~~utilizing ofhydrogen ~~our~~and HThydrogen-~~PEMs~~rich ~~relative~~fuels, the project aims to ~~LT-PEMs~~set ~~include:~~new benchmarks for energy resilience and environmental sustainability.

•Advent Technologies Wewill ~~have~~play ~~developed~~a ~~our~~pivotal ~~products~~role ~~under~~in the ~~principle~~project ofas ~~“Any~~the ~~Fuel~~primary technology provider, focusing on system integration and innovation. The ~~Anywhere~~key deliverable is a 50 kW High-Temperature Proton Exchange Membrane Fuel Cell (HT-PEM FC) dual-fuel portable power generator system.” This ~~which~~system ~~can~~will beconsist ~~distilled~~of ~~into~~a ~~the~~generator ~~two~~module ~~components:~~and a fuel tank, each housed in separate 20-foot containers for optimal mobility and deployment.

○ Any Fuel: While LT-PEMs require high-purity hydrogen to operate, our HT-PEMs can utilize low cost and abundant hydrogen-carrier fuels, including methanol, natural gas, e-fuels, liquid organic hydrogen carriers, dimethyl ether, and renewable biofuels. The infrastructure required for clean energy powered solely by high-purity hydrogen would cost trillions of dollars. In contrast, many of the hydrogen-carrier fuels can use existing or in-development infrastructure and have a much lower transport cost than hydrogen. This key technology differentiator bypasses the need to commit to a specific energy distribution network and leverages existing infrastructure. Most importantly, it provides an immediately serviceable market today, while we believe many LT-PEM competitors may have to wait another decade for the availability of green, high-purity, inexpensive hydrogen, and potentially longer for the maturity of hydrogen transportation and storage networks. Given the urgency to decarbonize power generation, and the investment challenges faced by developing countries, we expect methanol to have an increasingly significant role as a liquid hydrogen carrier and a low or no carbon dioxide emission alternative to oil.69

○Table ~~Anywhere: Our HT-PEM fuel cells have the ability to operate in a variety~~ of practical conditions, including a wide range of geographies, weather, ambient temperatures (as low as -20oC and up to +55oC), and in humid or polluted environments. LT-PEM fuel cells, on the other hand, tend to struggle in the heat, can be damaged by dry climates, or polluted air, and cannot handle impurities of the hydrogen supply. LT-PEM technology is intolerant to CO damage (with performance degradation at levels as low as 10 ppm), while HT-PEM can withstand 1-4% CO concentrations, depending on temperature and operation. For example, readily available low-cost hydrogen can be made with 1-2% carbon monoxide (20,000ppm), which works well with HT- PEMs. LT-PEM loses performance with only 10ppm of carbon monoxide. The relative durability of our products in a range of environments also provides a longer life of operation relative to LT-PEM fuel cells.Contents

• Our HT-PEM technology significantly reduces the balance of plant requirements of a fuel cell system relative to LT-PEM fuel cells. This means that fuel cells using our HT-PEMs have simplified requirements for supporting components and auxiliary systems, which enables reduced cost and increases application range for the end-user. It does this through two methods:RHyno Project

○The Advent ~~Superior~~Renewable ~~Heat~~Hydrogen ~~Management:~~Innovative ~~HT-PEM~~Technologies ~~fuel~~(RHyno) ~~cells~~project ~~operate~~involves atthe ~~high~~establishment ~~temperatures~~of ~~(between~~infrastructure ~~160°C~~for developing and ~~220°C~~manufacturing innovative fuel cells, ~~with~~electrolysers, ~~next-generation~~and ~~MEA~~their key components including Advent ground-~~based~~breaking ~~fuel~~Membrane ~~cells~~Electrode ~~operating~~Assembly ~~between~~technology at ~~80°C~~a ~~and~~megawatt ~~240°C~~(MW) scale. ~~Therefore,~~RHyno aims to pioneer the ~~temperature~~use ~~differential~~of ~~between~~innovative amaterials ~~HT-PEM~~to ~~fuel~~enhance ~~cell~~power density and lifespan while significantly reducing the ~~outside~~weight ~~environment~~and isvolume ~~large.~~of Aspower systems through a streamlined balance of plant.

51The planned state-of-the-art facility is designed to optimize production processes, boost efficiency, and industrialize fuel cell and electrolyser technologies. These advancements are essential for decarbonizing carbon intense industries, such as the aviation, maritime and heavy-duty automotive sectors, with further potential for spillover to other sectors, positioning Advent at the forefront of the clean energy transition.

~~TABLE~~The Fuel OFCell ~~CONTENTS~~Market

~~result,~~Fuel cell ~~only~~and ahydrogen ~~small~~technology ~~radiator,~~are ~~similar~~expected orto ~~smaller~~play ~~than~~a ~~the~~critical ~~radiator~~role in anglobal ~~ICE vehicle,~~decarbonization. isIn ~~needed~~order to ~~transfer~~meet ~~heat~~the ~~away~~targets ~~from~~established in the ~~fuel~~Paris ~~cell~~Climate ~~stack. Conversely~~Accords, ~~because~~which ~~LT-PEM~~seek ~~fuel~~to ~~cells~~mitigate ~~run~~climate ~~relatively~~change ~~cooler~~and ~~(under~~maintain 85global temperatures less than 1.5°C),-2.0°C above apre-industrial ~~significantly~~levels, ~~larger~~the ~~radiator~~international iscommunity ~~required~~will need to ~~effectively~~accelerate ~~maintain~~the ~~suitable~~adoption ~~operating~~of ~~temperatures~~technologies ~~and~~like our fuel cells that ~~conditions~~reduce ~~for~~or aneliminate ~~LT-PEM~~emissions ~~fuel~~of ~~cell~~carbon dioxide and other greenhouse gases.

○In addition, ~~Water~~the ~~Management~~challenges ~~Issues:~~associated ~~HT-PEM~~with ~~fuel~~existing ~~cells~~battery ~~use~~technology ~~phosphoric~~limit ~~acid~~it asfrom mass adoption across industries. Globally, an ~~electrolyte~~average of ~~rather~~$38 ~~than~~billion ~~water-assisted~~per ~~membranes~~annum is expected to be invested in the hydrogen and fuel cell sector between 2020 and 2040 to increase production capacity while significantly lowering the cost of manufacturing. ~~Therefore,~~While ~~they~~the ~~reduce~~availability of hydrogen limited the ~~need~~fuel cell industry in the past, it is now expected to become an opportunity for ~~water~~growth, ~~balance~~particularly ~~and~~in ~~other~~sectors ~~compensating~~such ~~engineering~~as ~~systems~~industrials, power generation, and automotive.

~~Our~~We believe ~~Solution~~that fuel cells will be a key component of the future energy generation platform given that:

~~Our~~● ~~core~~Fuel ~~product~~cells ~~offering~~generate ~~include:~~electricity and heat from hydrogen-based fuels, thereby substantially reducing emissions of carbon dioxide and other pollutants generated by the combustion process in internal combustion engines (“ICE” or “ICEs”) and diesel generators. Fuel cells can be powered autonomously for hours or days when the fuel comes from a discrete source or for longer when there is a pipeline or other large available source of fuel, such as a tank.

1.● ~~Systems:~~ Fuel cells ~~for~~utilize ~~portable~~fuels with a high energy density relative to lithium-ion batteries and ~~stationary~~other ~~applications~~battery oftechnology (according to ARPA-E power ~~generation~~densities, inhydrogen ~~the~~contains ~~range~~40,000 ofWh/kg ~~20W~~while tolithium-ion ~~20kW~~batteries carry only about 260Wh/kg). ~~These~~This makes fuel ~~cells~~cell ~~have~~technology ~~applications~~well-suited infor ~~the~~use ~~telecom~~in ~~tower~~heavy-duty mobility (~~e.g.~~marine, 5Gaerospace, 4Gtrucks) ~~power,~~and ~~surveillance,~~off-grid ~~defense~~energy ~~(and~~generation ~~other~~applications ~~portable~~where ~~power~~battery ~~applications),~~technology ~~energy~~faces ~~(and~~limitations ~~other~~such ~~critical)~~as ~~infrastructure~~lifespan, ~~and~~self-discharge, ~~auxiliary~~weight ~~power~~ (~~marine,~~for ~~leisure)~~longer ~~markets.~~run ~~Our~~times or higher power outputs, fuel cells are ~~manufactured~~between in3 ~~the~~to ~~U.S.,~~25 ~~Denmark,~~times ~~and~~lighter ~~Germany.~~than ~~Fuel~~batteries ~~cell~~providing ~~systems~~equivalent ~~provide~~power), ~~the~~operation ~~majority~~under ofalmost ~~our~~any ~~current~~weather ~~revenue~~conditions, and recharge times.

2.● ~~The~~Hydrogen ~~next~~is ~~generation~~already ofused ~~our~~to ~~fuel~~create ~~cells~~liquid, insynthetic ~~the~~fuels ~~15kW~~(eFuels tolike ~~1MW range~~e-Methanol, ismade ~~expected~~by tocombining ~~target~~hydrogen ~~the~~with ~~mobility~~carbon ~~sector~~dioxide ~~(e.g.,~~for ~~heavy~~a net-~~duty~~zero ~~automotive,~~liquid ~~mining~~fuel) ~~equipment,~~that ~~marine,~~have ~~aerospace,~~the ~~and~~advantage ~~unmanned~~of ~~aerial~~lower ~~vehicles~~transportation ~~(“UAV”)).~~costs Weand ~~are~~network ~~planning~~infrastructure investment relative to ~~enter~~hydrogen ~~into~~gas. ~~joint~~Interim ~~development~~fuels ~~agreements~~like ~~with~~methanol ~~Tier~~produced 1from ~~suppliers~~natural ~~and~~gas ~~OEMs~~have become subject to ~~bring~~increasing ~~HT-PEM~~interest ~~fuel~~worldwide ~~cells~~because tothey ~~the~~are ~~mobility~~currently ~~market~~available, cleaner, and less expensive than diesel. We ~~intend~~believe e-Methanol has the potential to bebecome a ~~provider~~leading ofzero-emissions ~~MEAs~~liquid ~~and~~fuel ~~core~~that ~~technology~~can ~~via~~leverage ~~licensing,~~the ~~rather~~current ~~than~~global ~~producing~~infrastructure ~~end-products~~from ~~for~~gas ~~the~~stations ~~mobility~~to ~~industry~~fuel tankers and trucks. ~~Revenue~~Given ~~from~~the ~~joint~~urgency ~~development~~to ~~agreements~~decarbonize ~~may~~power ~~include~~generation ~~engineering~~and ~~fees~~the ~~during~~challenges the ~~1-3~~investment ~~year~~requirement ~~initial~~poses ~~development~~for ~~cycle~~developing countries, ~~MEA~~we ~~sales,~~expect methanol to have an increasingly significant role as a liquid hydrogen carrier and ~~on-going~~a ~~licensing~~low/no ~~fees~~carbon dioxide emission alternative to oil.

3. We are a developer of the key component of the fuel cell, the MEA. The operation of the MEA is key to the functionality and characteristics of a fuel cell system. Our MEA enables a robust, long-lasting, and ultimately low-cost fuel cell product, relative to LT-PEM technologies. In addition to our fuel cell system offerings, our MEA is also a discrete product offering to third-party fuel cell manufacturers. MEA sales are expected to be a rapidly growing market in the future as more and more fuel cells are deployed globally by third parties, especially in the mobility space.70

~~Our~~Table ~~Business~~of ~~Outlook~~Contents

~~In 2021, we became publicly listed on NASDAQ. We acquired UltraCell~~The LLC (“UltraCell”), which spearheaded our product offering in the portable and defense markets. In the defense sector, we deliver human portable systems. In addition, the UltraCell portable system is being repurposed to provide remote power to oil and gas wellheads (Advent MHigh-~~ZERØ~~Temperature ~~family~~PEM ofFuel ~~products)~~Cell and to address the critical problem of methane emissions in Canada and the U.S. Furthermore, the Company has continued with delivery of MEAs to fuel cell manufacturers in Asia and with delivery of electrodes to the high-growth redox flow-battery market. We are also part of a consortium that has applied to develop “White Dragon,” the seminal large-scale decarbonization project in Southern Europe. We were selected Technology

52Our fuel cells are developed with the general concept of using “Any Fuel. Anywhere.” because of the HT-PEM technology we have pioneered since 2006. HT-PEM fuel cells have the advantage of operating with multiple low-carbon fuels (in addition to hydrogen), better heat exchange management, and efficiency, and they operate reliably under extreme conditions. Our high-temperature fuel cells operate between 80°C and 240°C, unlike typical LT-PEM fuel cells that are limited to below 100°C. This temperature advantage allows the fuel cell to work with other fuels and to have reliable operation at extreme conditions, which we believe are both significant competitive advantages for the stationary power generation market.

~~TABLE~~Within the OFfuel ~~CONTENTS~~cell market, our products have significant advantages relative to those of our competitors, who are focused on low-temperature proton exchange membrane technology (“LT-PEM” or “LT-PEMs”). We believe these advantages will help us secure commercial opportunities in the fuel cell market and help drive the widespread adoption of fuel cell technology.

byA. “Any ~~the~~Fuel”: ~~Greek~~Advent’s ~~Ministry~~HT-PEM offuel ~~Development~~cells ~~and~~are ~~Investment~~designed to be ~~part of the first wave of Important Projects of Common European Interest (“IPCEI”) on Hydrogen, which is currently pending European Union approval.~~multifuel

~~In September 2021, we completed the acquisition of SerEnergy A/S (~~“~~SerEnergy~~e-Fuel-ready”): While ~~and~~LT-PEMs ~~fischer~~require ~~eco~~high-purity ~~solutions~~hydrogen ~~GmbH~~to ~~(“FES”)~~operate, aour ~~leading~~HT-PEMs ~~manufacturer~~can ofutilize ~~fuel~~low-cost ~~cell systems, with thousands of systems shipped in recent years. SerEnergy is located in Denmark~~ and ~~FES~~abundant ishydrogen-carrier ~~located~~fuels, ~~in Germany. The acquisition effectively~~including ~~doubled~~methanol, ~~our~~natural ~~team~~gas, ~~to over 170 people~~eFuels, ~~and~~hydrogen weextracted ~~believe~~from ~~the~~liquid ~~acquired~~organic ~~business~~hydrogen ~~will~~carriers, bedimethyl aether, ~~strong~~and ~~pillar~~renewable ~~of its potential growth strategy~~biofuels. ~~SerEnergy~~We ~~and FES~~ have focused ~~significant~~on ~~production~~optimizing ~~capabilities, are expected to benefit significantly from~~ our ~~next-generation~~ ~~MEAs~~fuel ~~and~~cells ~~are~~for ~~expected~~methanol, ~~to provide~~ a ~~very~~liquid ~~strong~~green ~~foothold~~hydrogen ~~in the off-grid market~~carrier. ~~SerEnergy~~Methanol ~~systems,~~comes ~~primarily~~ in ~~the~~three ~~5kW~~main ~~range, target the telecoms industry (especially the growing 5G tower demand) and other diesel generator replacement off-grid markets.~~forms:

~~Our~~● ~~growth~~Gray ~~strategy~~(natural-gas-based) methanol is ~~focused~~the onmost ~~targeting~~promising ~~the~~interim ~~following~~semi-clean ~~four sectors:~~alternative to diesel.

•Advantages: 40% ~~The~~lower ~~stationary~~CO2 ~~off-grid market~~emissions, ~~expected~~lower toprice bethan adiesel, ~~growing~~no ~~market~~NOx, SOx.

•● ~~The~~Biomethanol ~~human-portable~~is ~~defense,~~currently ~~surveillance, energy infrastructure, and leisure market based on UltraCell’s innovative products~~available.

•Advantages: 80% ~~The~~lower ~~development~~CO2 ofemissions, ~~next-generation~~lower ~~MEA~~price ~~and~~than ~~fuel~~diesel, ~~cell~~no ~~solutions~~NOx, ~~for the mobility market~~SOx.

•● ~~The large~~e-~~scale~~Methanol ~~fuel~~is ~~cell~~already ~~systems~~under ~~market~~production, ~~(power~~with ~~generation~~approximately ~~and~~78 ~~power~~projects tounderway ~~gas)~~globally, ~~especially~~aiming ~~following~~to ~~developments~~produce in11.7 ~~the~~million ~~multi-billion~~tones ~~euro~~by ~~“White~~2028. ~~Dragon”~~eMethanol ~~project~~is ~~(in~~produced ~~which~~from ~~Advent~~green ishydrogen ~~the~~and ~~fuel~~is, ~~cell development partner)~~therefore, ifa ~~approved~~green byliquid ~~the European Union~~fuel.

Advantages: 80% lower CO2 emissions, lower price than diesel, no NOx, SOx.

To date, Advent has delivered over 1,200 of these systems, totaling 731,274 operational hours and consuming 1.2 million liters of methanol (as of March 2024). These systems serve telecom towers, critical infrastructure, and defense applications, capitalizing on logistical simplicity and the advantages of fuel availability.

“Enhanced Market Opportunity”: The infrastructure required for clean energy powered solely by high-purity hydrogen would cost trillions of dollars. In contrast, many of the hydrogen-carrier fuels, like e-Methanol, can use existing or in-development infrastructure and have a much lower transport cost than hydrogen. This key technology differentiator bypasses the need to commit to a specific energy distribution network and leverages existing infrastructure. Most importantly, it provides an immediately serviceable market today, while we believe many LT-PEM competitors may have to wait at least another decade for the availability of green, high-purity, inexpensive hydrogen, and potentially longer for the maturity of hydrogen transportation and storage networks. Given the urgency to decarbonize power generation and the investment challenges developing countries face, we expect e-Methanol to have an increasingly significant role as a liquid hydrogen carrier and a low or no carbon dioxide emission alternative to oil.

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Production of green hydrogen remains very expensive. In addition, the cost to transport and distribute green hydrogen is exceptionally high in the same range as the cost of production, and with significant losses, whether liquification, compression, or conversion to ammonia, is considered. Compared to the above, e-Methanol can be produced by combining green hydrogen with CO2 using well-known synthesis processes and creating a liquid green fuel that can be transported, stored, and distributed through established global logistics networks. For example, a gas station would require minimal modifications to be able to dispense methanol, while by comparison, a hydrogen station would require an investment of millions and a new location.

Therefore, Advent’s fuel cells optimized for e-Methanol are highly suitable for applications where liquid fuel is preferable, and the transportation of hydrogen or batteries (requiring frequent recharging) is highly inefficient. Such applications are off-grid power, telecom tower power, shipping, off-grid charging stations, bad-grid infrastructure, defense, security, emergency response missions, and generally, any area where a diesel generator or a heavy portable battery has applications. We believe decreasing fuel cell costs due to technology innovation and manufacturing scale-up can allow us to grow in the power generation market and potentially displace diesel generators in applications with a clear total cost of ownership value proposition, in addition to the environmental mandate.

B. Anywhere: Advent’s HT-PEM fuel cells are designed to work under extreme conditions

Extreme Weather Conditions: Our HT-PEM fuel cells can operate in various practical conditions, including a wide range of geographies, weather, ambient temperatures (as low as -20oC and up to +55oC), and in humid or polluted environments. On the other hand, LT-PEM fuel cells tend to struggle in the heat, can be damaged by dry climates or polluted air, and cannot handle the impurities of the hydrogen supply.

Superior Heat Management: HT-PEM fuel cells operate at high temperatures (between 160°C and 220°C, with next-generation MEA-based fuel cells operating between 80°C and 240°C). Therefore, the temperature differential between an HT-PEM fuel cell and the outside environment is large. As a result, only a small radiator, similar to or smaller than the radiator in an ICE vehicle, is needed to transfer heat away from the fuel cell stack. Conversely, because LT-PEM fuel cells run relatively cooler (usually under 85°C), a significantly larger radiator is required to effectively maintain suitable operating temperatures and conditions for an LT-PEM fuel cell.

The heat management advantage makes HT-PEMs ideal for the aerospace and heavy-duty truck sectors, among others. An aircraft flying in hot weather, over 35°C, a truck in Arizona or India operating in such high outside temperatures, would need a high to prohibitive amount of power to be wasted just for cooling down, rendering competitive technologies inefficient.

This advantage has been the key reason that Advent has had success in establishing strategic relationships with companies in the Aerospace and Automotive sector, such as the Joint Development Agreements with Airbus and Hyundai, as well as multiple Technology Assessments (which we aim to convert to Joint Development Agreements or Technology License Agreements) with other world-leading companies in these two fields.

●

Fuel and Air Quality Tolerance: Fuel cell systems take hydrogen and air as inputs. Any low-quality intake, even in one instance, may destroy an LT-PEM fuel cell. LT-PEM technology is intolerant to CO damage (with performance degradation at levels as low as 10 ppm), while HT-PEM can withstand 1-4% CO concentrations, depending on temperature and operation. For example, readily available low-cost hydrogen can be made with 1-2% carbon monoxide (20,000ppm), which works well with HT-PEMs. LT-PEM loses performance with only 10 ppm of carbon monoxide. The relative durability of our products in a range of environments also provides a longer life of operation relative to LT-PEM fuel cells.

●

Water Management Issues: HT-PEM fuel cells use phosphoric acid as an electrolyte rather than water-assisted membranes. Therefore, they reduce the need for water balance and other compensating engineering systems.

●

Simplified Design for Manufacturing: Our HT-PEM technology significantly reduces the balance of plant requirements of a fuel cell system relative to LT-PEM fuel cells due to the water, heat management, and air/fuel advantages described above. This means that HT-PEMs have simplified requirements for supporting components and auxiliary systems, which enables reduced cost and increases application range for the end-user.

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The Advent MEA

In order to achieve high-temperature operation, we develop highly differentiated chemistry components, the MEAs. In particular, we are developing a new Advanced MEA (“Advent MEA”). The Advent MEA has been developed in collaboration with the U.S. DoE after we were awarded the L’Innovator commercialization program. Under this program, we are working closely with the Los Alamos National Laboratory (LANL), Brookhaven National Laboratory (BNL), and National Renewable Energy Laboratory (NREL), to commercialize the decade-long materials advancements in the field of MEA development. We expect that these next-generation MEAs will bring the HT-PEM technology into the mobility area by enabling fuel cells to be lightweight with high-power density. The Advent MEA is also anticipated to eventually deliver as much as three times the power output and lifetime versus the current MEA product. While we are already projecting being able to pass through substantial cost benefits to its customers through economies of scale as it increases MEA production, the successful development of the Advent MEA will be an important factor in delivering the required improvement in cost-effective performance to our customers.

We believe that Advent stands at the forefront of revolutionizing the global fuel cell market with its groundbreaking Advent MEA technology, which has been developed through strategic collaborations with esteemed institutions such as Los Alamos, Brookhaven, and the National Renewable Energy Laboratories. In August 2023, Advent was honored to receive the prestigious Richard P. Feynman Innovation Prize for Technology Transfer Excellence from the U.S. Department of Energy’s Los Alamos National Laboratory, recognizing the groundbreaking potential of Ion Pair MEAs. Similarly, in November of 2024 Advent and Los Alamos National Laboratories were listed as being among the top 100 R&D technologies worldwide. These MEAs have demonstrated exceptional performance in challenging applications, particularly in heavy-duty mobility. They are promising to match LT-PEM in power density and lifetime and offer unparalleled versatility for a wide range of applications due to their ability to operate from 80°C to 200°C. The technology’s heat rejection capabilities render it ideal for aerospace and truck markets. Through ongoing Joint Development Agreements with renowned global enterprises such as Airbus and Hyundai Motor Company, Advent focuses on integrating its Advent MEA technology into their fuel cell projects. Simultaneously, Advent has engaged in technology assessments with five additional global leaders to expedite HT-PEM MEA development for mobility markets. By combining LT-PEM’s power density potential with HT-PEM’s resilience and multifuel capability, we believe Advent MEAs offer increased operational lifetimes and the ability to operate at far higher current densities compared to existing high-temperature MEAs. Advent holds unique intellectual property rights over the core technology and the manufacturing scale-up of the MEA. HT-PEM fuel cells featuring Advent’s Advent MEA aim to offer tripled lifespan and power density compared to previous products. The anticipated result of significant improvements in lifetime and power density is expected to dramatically reduce the total cost of ownership of Advent’s fuel cell solutions. Advent has established resources in the USA and Europe to mass-produce the Advent MEA and is expanding its partner network to license our hardware technology. Framework agreements are under negotiation with end-users, as well as licensing agreements with Tier 1 manufacturers and global leaders in stationary and off-grid power equipment. Joint Development Agreements with the aerospace, marine, and automotive sectors are expected to accelerate the Ion Pair MEA technology in 2025 and 2026, with commercial scale-up planned for late 2026. Additionally, the Defense solution under development (Honey Badger 50) is also expected to transition to mass production by 2026.

Acquisitions and Other Significant Milestones

Advent Technologies LLC: Advent and U.S. Department of Defense (the “US DoD”) are in constant discussions during the progress of ongoing programs with ENVISION, and we have received the green light from the US DoD to make additional proposals for new programs focusing on further improvement of Honey Badger product on one hand and also leveraging its manufacturability towards mass production.

We have significantly streamlined our product, system integration, manufacturing, and testing capabilities, avoiding duplication and abandoning less promising product development efforts to manage costs better. During this process, we have significantly reduced personnel and support activities in certain locations where overlap existed after the acquisitions.

Advent’s Livermore subsidiary brings Silicon Valley-type innovation. Ion Pair MEA technology brings a significant advantage toward reducing cost and increasing the performance of our systems. Our investment plan reflects its strategic goal to assemble significant global know-how of the HT-PEM industry.

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Following the expected availability of EU Innovation funds from the RHyno Project, we will expand R&D operations in the selected region of Western Macedonia, Greece. We expect to focus future activity plans in Greece and the USA (for MEA and defense-market-related reasons) while product development efforts will be across the USA and Greece.

Business Strengths

~~Simplified~~Highly Differentiated ~~balance of plant technology~~Technology: ~~Our~~We ~~HT-PEM~~believe ~~technology~~that ~~significantly~~for ~~reduces~~ the ~~balance~~reasons ofexplained ~~plant~~above, ~~requirements~~HT-PEM ofis a ~~fuel~~highly ~~cell~~differentiated ~~system~~technology ~~relative~~that provides tosignificant ~~LT-PEM~~competitive ~~fuel~~advantages ~~cells.~~to ~~Fuel~~Advent ~~cells~~and ~~utilizing~~ our ~~technology~~partners. ~~have~~HT-PEM ~~simplified~~technology ~~requirements~~is ~~for~~a ~~supporting components~~new and ~~auxiliary~~promising ~~systems~~technology ~~because~~when ~~they~~compared to ~~reduce~~LT-PEM ~~the~~(Low ~~complexity~~Temperature ofProton ~~water~~Exchange ~~management~~Membrane), ~~systems.~~that ~~Our~~was ~~technology~~developed ~~enables~~for ~~advanced,~~the ~~low-cost~~last ~~and~~50 ~~simplified~~years ~~cooling technology,~~ and ~~increases~~may ~~the~~have ~~application~~plateaued ~~range~~in ~~for~~terms ~~the~~of ~~end-user. This is~~expected ~~especially~~technology ~~important~~breakthroughs ~~for~~needed ~~air,~~to ~~heavy-duty~~overcome ~~transportation,~~thermal control and ~~marine~~environmental ~~applications~~limitations.

~~Leveraging~~Experienced management ~~existing~~team ~~fuel~~with ~~infrastructure:~~a ~~Given~~proven ~~the~~track ~~fuel-flexible~~record: ~~nature~~We ofwere ~~our~~founded ~~technology,~~and wemanaged ~~are~~by ~~able~~world-class toelectrochemists, ~~leverage~~material ~~the~~scientists, and ~~existing~~ fuel ~~delivery~~cell ~~infrastructure~~specialists –with ~~e.g.~~significant ~~around~~industry ~~3 million~~and ~~miles~~manufacturing ofexpertise. ~~natural~~We ~~gas~~have ~~pipelines connecting~~received ~~production,~~numerous ~~storage~~R&D ~~and~~funds ~~distribution~~from ~~systems~~the inUS DoE and the ~~U.S.~~European –Union toand ~~deliver~~are ~~power~~considered to a ~~wide~~pioneer ~~range~~with years of ~~customers~~experience ~~and~~in ~~markets~~clean ~~today~~energy technology innovation. ~~Our~~The ~~plug-and-play~~team ~~dynamic~~that we ~~enables~~have ~~swift~~recruited ~~“time-~~to~~-market”~~ ~~capabilities.~~bring Byinnovation ~~contrast,~~to the ~~infrastructure investment~~fuel ~~required~~cell ~~for~~industry is highly experienced and has a ~~high-purity~~long ~~hydrogen~~pedigree ~~economy~~in isR&D ~~expected~~and toworld-class manufacturing. beOur ~~significant~~team –has ~~approximately~~been ~~$15~~developing ~~trillion~~MEA ~~between~~components ~~now~~since 2006 and ~~2050~~is ~~globally~~led by Dr. Emory De Castro (CTO).

~~Experienced management team with proven track~~Strategic ~~record:~~Partnership ~~The team that we have recruited to bring innovation to the fuel cell industry is highly experienced~~ with aUS ~~long~~DoE ~~pedigree in R&D~~ and ~~world-class~~Los ~~manufacturing.~~Alamos ~~Our~~National ~~team~~Laboratories: ~~has been developing MEA components since 2006 and is led by Dr. Emory De Castro (CTO) who has significant industrial experience.~~ In addition, we initiated in 2021 a ~~joint~~Cooperative ~~development~~Research ~~effort~~and Development Agreement (CRADA) under the U.S. Department of Energy (“DoE”) umbrella to commercialize next-generation MEAs and ultra-low platinum catalyst solutions developed by the National Laboratories at Los Alamos, ~~NREL Laboratories~~Brookhaven, and ~~Brookhaven~~NREL, ~~Laboratories~~ in the U.S. We were selected as the scale-up and commercialization partner of the DoE and isare working closely with the highly-skilled R&D teams of top U.S. ~~labs~~government laboratories.

~~Following~~MEA IP ~~the acquisitions of UltraCell, SerEnergy~~ and ~~FES,~~Technology: ~~and~~We ~~its ongoing~~firmly ~~recruiting~~believe ~~and development~~ in the ~~U.S.~~transformative ~~(including~~potential of the ~~new~~Advent ~~product~~MEA ~~development~~to ~~facility,~~redefine ~~close~~the toglobal ~~Harvard~~fuel ~~and~~cell ~~MIT~~market, enabling ~~under~~applications ~~construction~~that inwere ~~Charlestown,~~previously ~~Massachusetts~~unattainable ~~that~~with isconventional ~~expected~~fuel tocell ~~open~~materials. inOur ~~2022),~~objective weis ~~have~~to ~~significantly~~enhance ~~increased~~the ~~our~~MEA’s ~~product,~~capabilities ~~system~~when ~~integration,~~operating ~~manufacturing,~~at ~~and~~160°C ~~testing~~to ~~capabilities.~~180°C ~~UltraCell~~for ~~brings~~more ~~Silicon~~than ~~Valley-type~~20,000 ~~innovation~~hours, ~~while~~delivering ~~SerEnergy’s~~a ~~expertise~~higher ~~and~~power ~~world-class~~density ~~reputation~~that will result in ~~the~~a ~~stationary~~simpler, ~~fuel~~more ~~cell~~cost-effective ~~industry~~system iswith ~~well~~superior ~~established.~~performance ~~Our~~in ~~team~~terms ~~now numbers~~of ~~over~~weight, ~~200~~power, ~~people~~lifetime, ~~many~~total ~~with~~cost ~~more than a decade~~ of ~~hands-on~~ownership, ~~expertise~~and infrastructure ~~in the HT-PEM market~~investment. ~~Our~~As ~~investment~~we ~~plan~~continue ~~reflects its strategic goal~~ to ~~assemble~~strengthen ~~significant~~our ~~global~~collaborations ~~know-how~~with some of the ~~HT-PEM~~world’s ~~industry.~~largest WeOEMs ~~expect~~and ~~that~~Tier ~~HT-PEM,~~1 ~~with~~Manufacturers, ~~technology~~our ~~initially~~aim ~~developed~~is ~~decades~~to ~~after~~capitalize ~~LT-PEM,~~on isthe ingrowing ~~early~~momentum ~~stages~~and ofdemand ~~growth~~for asour ~~compared to LT~~HT-PEM, a technology ~~initially developed during the 1960s~~.

53Products and Services

~~TABLE~~We derive OFrevenue ~~CONTENTS~~from the following sources:

1. Engineering and License Fees: In the mobility sector (e.g., heavy-duty automotive, mining equipment, marine, aerospace), we are entering into Joint Development Agreements (“JDAs”) (as in the case of Hyundai and Airbus) to develop joint solutions for specific sectors. We plan to enter into Technology License Agreements (“TLAs”) to allow 3rd party Tier 1 manufacturers or world-leading companies to market the licensed Advent technology in exchange for a license fee. We intend to be a provider of MEAs and core technology via licensing rather than producing complete fuel cells for the mobility industry. Revenue from JDAs may include engineering fees during the 1-3 year initial development cycle (“JDA fees”), MEA sales, and ongoing licensing fees.

~~Our~~2. ~~fuel~~MEA ~~cells~~Sales: ~~can~~We ~~use~~develop ~~“Any~~and ~~Fuel.~~manufacture ~~Anywhere.”~~the ~~because~~critical component of the ~~HT-PEM technology~~fuel ~~that~~cell, wethe ~~have~~MEA. ~~pioneered~~The ~~since~~operation ~~2006.~~of ~~High-temperature~~the ~~fuel~~MEA ~~cells~~is ~~currently~~key ~~operate~~to atthe ~~high~~functionality ~~temperatures~~and ~~(between~~characteristics ~~160°C~~of ~~and~~a ~~220°C)~~fuel ~~and~~cell ~~have~~system. ~~the~~In ~~potential~~addition to ~~operate~~our ~~between~~fuel ~~80°C~~cell ~~and~~system ~~240°C~~offerings, ~~unlike~~our ~~typical~~MEA ~~LT-PEM~~is ~~fuel~~a ~~cells~~discrete ~~that~~product ~~are~~offering ~~limited~~ to ~~below~~third-party ~~100°C~~manufacturers. ~~This~~MEA ~~temperature~~sales ~~advantage~~are ~~allows~~expected ~~the~~to ~~fuel~~be ~~cell~~a torapidly ~~work~~growing ~~with~~market ~~other~~as ~~fuels~~more ~~and~~fuel tocells ~~have~~are ~~reliable~~deployed ~~operation~~globally atby ~~extreme~~third ~~conditions~~parties, ~~which~~especially wein ~~believe is a significant competitive advantage for~~ the ~~stationary~~mobility ~~power generation market~~space.

~~Enhanced~~3. ~~market~~Fuel ~~opportunity:~~Cell ~~The~~Systems ~~multi-fuel~~and ~~capability~~Stacks: ~~enables~~As usour toJDAs ~~have~~mature aand ~~very~~move ~~strong~~to ~~position~~manufacturing inpartnerships ~~the~~we ~~off-grid~~expect ~~and~~to ~~portable~~derive ~~power~~revenue ~~market~~from infuel ~~select~~cell ~~applications~~systems ~~like~~and ~~telecom~~stacks ~~towers~~for portable and ~~critical~~stationary ~~infrastructure~~ power ~~needs.~~generation ~~In these~~ applications, ~~diesel~~range ~~generators~~from ~~are~~20W ~~primed for replacement for environmental and cost reasons, batteries are unable~~ to ~~provide a long-term year-round solution, and hydrogen presents difficult logistical concerns~~MWs. WeThese ~~believe fuels like methanol are a more compelling choice and that our HT-PEM~~ fuel cells ~~are~~have ~~highly suitable for these~~ applications. Wein ~~believe~~the ~~decreasing~~data ~~fuel cell costs~~center, ~~due~~commercial ~~to technology innovation~~ and ~~manufacturing~~industrial ~~scale-up~~backup, ~~can~~telecom ~~provide~~tower usand ~~with~~other ancritical ~~opportunity~~infrastructure to(e.g., ~~grow in~~5G, ~~the~~4G) power, ~~generation~~defense ~~market~~ (and ~~potentially~~other ~~displace~~portable ~~diesel~~power ~~generators in~~ applications), ~~with~~and aheavy-duty ~~clear~~mobility ~~total~~(automotive ~~cost~~trucks, ~~of ownership value proposition~~aviation, inmarine) ~~addition~~power ~~to the environmental mandate~~markets.

The next-generation of our fuel cells is being developed in collaboration with the U.S. DoE after we were awarded the L’Innovator commercialization program. Under this program, we are working closely with the Los Alamos National Laboratory (LANL), Brookhaven National Laboratory (BNL), and National Renewable Energy Laboratory (NREL), to commercialize the decade-long materials advancements in the field of MEA development. We expect that these next-generation MEAs (“Advanced MEA”) will bring the HT-PEM technology into the mobility area by enabling fuel cells to be lightweight with high-power density. The Advanced MEA is also anticipated to deliver as much as three times the power output of its current MEA product. While we are already projecting being able to pass through substantial cost benefits to its customers through economies of scale as it increases MEA production, the successful development of the Advanced MEA will be an important factor in delivering the required improvement in cost effective performance to our customers.74

~~Based~~Table on the several critical advantages offered by our HT-PEM technology over batteries and LT-PEM technology, we expect to be highly competitive in numerous applications. In particular, our HT-PEM fuel cells and MEAs are well-suited to off-grid power, portable power applications, combined heat and power, and mobility (e.g., heavy-duty automotive, aviation, mining equipment, marine, and UAV). Our goal is to partner with Tier 1 suppliers and OEMs in these new markets, focusing on the fuel cell technology development, licensing, and the mass production of ~~the next-generation MEAs.~~Contents

1. Off-Grid Power: We have a growing presence in the off-grid power market, with its recently acquired SerEnergy subsidiary having shipped thousands of systems worldwide to telecommunications providers for back-up power systems and stationary power sectors. Methanol is easier and cheaper to deliver to remote locations compared to pure hydrogen, providing our HT-PEM technology with an advantage in the off-grid market. Off-grid fuel cell solutions can use methanol already available at some remote industrial sites, like wellheads. Additionally, methanol can be found in products already present at some remote sites, such as certain windshield washer fluids. These products could be repurposed as a fuel source for the fuel cell. Fuel cells in these applications produce significantly less of the greenhouse gases compared to ICE generators and produce power without ICEs’ attendant high levels of nitrogen oxides, sulfur oxides or particulate emissions. Off-grid power solutions have the potential to run full-time, 365 days a year, 24 hours per day. Our launch of the M-ZERØ methanol-fueled low-power system targets the power generation needs of remote oil and gas locations. The current method of powering such equipment results in significant methane emissions that are equivalent to millions of cars’ emissions per year.Addressable Markets

2.Based on ~~Portable~~the ~~Power:~~several ~~Our~~critical ~~acquisition~~advantages ofoffered ~~Silicon~~by ~~Valley~~our HT-~~based~~PEM ~~UltraCell~~technology ~~provided~~over usbatteries ~~with~~and ~~complete~~LT-PEM ~~system~~ technology, ~~for~~we ~~the~~expect ~~portable~~to ~~power~~be ~~and~~highly ~~defense~~competitive in ~~markets~~numerous applications. ~~Electrification~~Our isHT-PEM ~~one~~fuel ofcells ~~the~~and ~~key~~MEAs ~~initiatives~~are inwell-suited ~~the~~to ~~defense~~off-grid ~~industry~~power, asportable ~~the~~power ~~needs~~applications, ~~for~~combined ~~mobility~~ heat and power, onand ~~demand~~mobility ~~are increasing dramatically~~(e.g., ~~Our~~heavy-duty ~~fuel~~automotive, ~~cells~~aviation, ~~have~~mining ~~already~~equipment, ~~been~~marine, ~~deployed~~and byUAV). ~~the~~Our USgoal ~~Department~~is ofto ~~Defense~~partner ~~(“DoD”),~~with inTier 1 ~~the~~suppliers ~~XX-55~~and ~~portable~~OEMs ~~power~~in ~~system,~~these ~~while~~new ~~the next-generation “Honey Badger” product~~markets, afocusing ~~wearable~~on fuel cell ~~designed~~technology todevelopment, ~~provide~~licensing, ~~soldiers~~and ~~with on~~ the gomass ~~power,~~production isof ~~currently in~~ the ~~DoD’s demonstration/validation program~~next-generation MEAs.

54Off-Grid & Backup Power: We have a strong presence in the off-grid power market, with our discontinued legacy product SereneU product offering having shipped about 1,200 systems worldwide to telecommunications providers for backup power systems and stationary power sectors. Methanol is easier and cheaper to deliver to remote locations compared to pure hydrogen, providing our HT-PEM technology with an advantage in the off-grid market. Off-grid fuel cell solutions can use methanol, which is already available at some remote industrial sites, like wellheads. Fuel cells in these applications produce significantly fewer greenhouse gases than ICE generators and produce power without ICEs’ attendant high levels of nitrogen oxides, sulfur oxides, or particulate emissions. Off-grid power solutions have the potential to run full-time, 365 days a year, 24 hours per day.

~~TABLE~~Portable Power OFfor ~~CONTENTS~~Construction, EV Charging Applications, and Events: In December 2023, Advent demonstrated a portable clean power solution designed for various applications, including construction sites, remote EV charging stations, events, and concerts. This innovative solution integrates both a battery and a fuel cell, operating seamlessly on liquid green fuels such as methanol, biomethanol, or eMethanol. Battery-only systems face challenges in off-grid applications as they require continuous relocation to the grid or alternative power sources for recharging. Diesel generators emit harmful emissions, noise, and pose risks of fuel theft. Pure hydrogen systems entail significant fuel sourcing, storage, and transportation costs in off-grid locations. Recognizing a specific market demand within the construction rental sector, particularly in anticipation of forthcoming regulations prohibiting diesel gensets.

Human-Portable Power: Our acquisition of Silicon Valley-based UltraCell provided us with complete system technology for the portable power and defense markets. Electrification is one of the key initiatives in the defense industry as the needs for mobility and power on demand are increasing dramatically. Our fuel cells have already been deployed by the US DoD, in the XX-55 portable power system, while the next-generation “Honey Badger” product, a wearable fuel cell designed to provide soldiers with on-the-go power, is currently in the US DoD’s demonstration/validation program.

Marine: In the marine industry, neither compressed hydrogen nor batteries are a viable option for commercial shipping. The industry is evaluating alternative fuels to replace bunker fuel, and methanol appears to be among the most likely hydrogen carriers positioned to meet the European Union’s 2050 decarbonization objectives. Our fuel cells are well-suited for methanol use, as the high-temperature operation can use low-grade hydrogen (converted from methanol via reformation) that does not work with current LT-PEM fuel cells. Applications in the marine industry are likely to develop initially in auxiliary power and smaller ships and eventually scale to the multi-MW range main propulsion market. Our fuel cells promise fuel flexibility with hydrogen gas, liquid organic hydrogen carriers, methanol, and natural gas and operate at high temperatures through proprietary chemistry. Marine applications could be scalable for divergent load requirements and applications such as powering the entire propulsion system or, alternatively, providing auxiliary power to a differently powered primary propulsion system. Marine fuel cell usage could offer long range and fast refill; unlike battery power, longer routes and larger vessels can be powered by fuel cells as compared to batteries. In addition, fuel cells can be used in a hybrid structure in conjunction with battery power. We are planning our initial focus on applications for auxiliary marine power, and then we plan to focus on the main power of vessels.

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The above markets define our current products, while the markets below constitute its largest opportunities for growth in the future:

3. Combined Heat and Power (“CHP”): By virtue of their high -temperature operation, HT-PEM fuel cells are well suited for delivering heat in addition to power to large commercial buildings and single or multi-family homes. The CHP efficiency is atin the 85%-90% range, making HT-PEM fuel cells ~~extremely~~highly efficient for such uses. HT-PEM fuel cells can be supplied by existing natural gas infrastructure and eventually by a future hydrogen-blend or pure-hydrogen pipeline network.

4. Automotive: Our Byfuel ~~charging~~cells ~~electric~~can ~~vehicles’~~work together with EV batteries, charging batteries on-board ~~through~~by ~~the~~converting ~~conversion of~~ high-purity hydrogen or hydrogen-carrier fuels into electricity, ~~our~~and ~~fuel~~thus ~~cells~~ solve the range and recharging issues that battery-only electric vehicles currently face. This issue is a particular challenge in heavy-duty and commercial vehicles. Since our fuel cells can use hydrogen-carrier fuels such as ~~natural~~eFuels ~~gas, methanol~~ and biofuels, ~~fuels that are of growing in importance in China, India, and Western Europe,~~ we believe that our technology ~~will~~can be critical in accelerating the mass adoption of electric vehicles and the shift away from ICEs. Existing battery and LT-PEM technology ~~are~~have ~~unable~~challenges toin ~~meet~~meeting ~~the needs of~~ heavy-duty transportation needs, which require long-range, heavy payloads, fast refill times, and the ability to operate in diverse environments. For example, LT-PEM fuel cells ~~are~~cannot ~~unable to~~ operate efficiently in hot environments because the radiator required to cool the MEA to the appropriate temperature range would be too large and ~~therefore~~ impractical. The use of battery-only technology has the added disadvantage of insufficient power capacity without a substantial volume and weight of batteries, which ~~results~~significantly inreduces ~~a significant reduction in~~ cargo capacity.

5Aerospace: The recent JDA with Airbus showcases the potential of HT-PEM technology for the Aerospace sector. ~~Aviation:~~The primary aim of our collaborative project is to expedite the advancement of Advent’s Ion Pair MEA technology, aligning it with aviation standards and anticipated technological thresholds. Our overarching objective is to assist Airbus in realizing its vision of propelling aircraft solely through fuel cells. Central to the project’s mission is addressing the requirements for future hydrogen-powered aircraft, emphasizing the potential for substantial weight and volume reduction in the powertrain system. This will be achieved through streamlining the balance of plant and cooling subsystems. We anticipate that our technology will play a pivotal role in realizing this milestone, potentially leading to widespread adoption across numerous aircraft in the near future. Given LT-PEM systems’ heat exchange issues, high-temperature operation in aviation is essential. In addition, our fuel cells can deliver a much longer range (autonomy) and better utilization (through faster time to refill and greater payload) for aircraft, commercial drones, eVTOLs, and auxiliary power for traditional aircraft than battery power alone can deliver. ~~Existing commercial drones based on battery-only technology have a limited flight time given the power limitations of the lightweight requirements of flight.~~ Compared to battery -powered flights, ~~aircrafts~~aircraft powered by fuel cells using next -generation HT-PEMs and ultra-lightweight non-metal plates could increase range, payload/passenger capacity, and the number of trips made on one charge or fill-up. HT-PEM aircraft have the potential to refuel significantly faster than an equivalent battery could recharge. The high-purity hydrogen currently required by LT-PEM is considered unsafe for widespread commercial use,. ~~while~~At the same time, our HT-PEM provides sufficient range using safer liquid fuels, and the Company believes it is ~~key~~critical to efficient real-world flight usage. Hydrogen gas and dimethyl ether are suitable for ~~use as~~ fuel for aviation fuel cells, and both work well with HT-PEM technology. ~~Additionally, high-temperature operation in aviation is essential, given heat exchange issues.~~ Fuel cells have shown that drones can stay airborne for longer ~~periods of time~~, ~~which~~enhancing ~~enhances~~ their value proposition and business applications. ~~We expect drone prototypes based on our technology to be available as soon as 2022.~~

6.Stationary Power ~~Marine:~~for InData ~~the~~Centers, ~~marine industry~~Microgrids, ~~neither~~and ~~compressed~~Buildings: ~~hydrogen~~With ~~nor batteries are~~ a ~~viable~~run-time ~~option~~of ~~for~~200 ~~commercial~~hours ~~shipping.~~per ~~The~~year ~~industry~~(serving isas ~~evaluating~~backup) ~~alternative~~and ~~fuels~~typical topower ~~replace~~generator sizes ~~bunker~~ranging ~~fuel,~~from ~~and~~1 ~~methanol appears~~ to be20MW, ~~among~~ the ~~most~~total ~~likely~~deployed ~~hydrogen~~capacity ~~carriers~~of ~~positioned~~power togenerators ~~meet~~in ~~the~~data ~~European~~centers ~~Union’s~~globally ~~2050~~stands ~~decarbonization~~at ~~objectives~~5.6GW. ~~Our~~This ~~fuel~~highlights a ~~cells~~substantial ~~are~~market ~~well-suited~~ for ~~methanol~~green ~~use,~~power asgeneration ~~the~~solutions, ~~high-temperature~~presenting ~~operation~~a ~~can~~unique ~~use~~opportunity ~~low-grade~~for ~~hydrogen~~Advent’s ~~(converted from methanol via reformation) that does not work with current LT-PEM~~ fuel cells. ~~Applications~~and inclean ~~the~~power solutions ~~marine industry are likely~~ to ~~develop~~be ~~initially~~widely deployed in ~~auxiliary power and smaller ships, and eventually scale to~~ the ~~multi-MW~~data ~~range~~center ~~main propulsion market~~industry. ~~Our~~There ~~fuel~~is ~~cells~~significant ~~promise~~potential ~~fuel~~for ~~flexibility~~mass ~~with~~adoption ~~hydrogen~~in ~~gas,~~data ~~liquid organic hydrogen carriers~~center, ~~methanol,~~ off-grid and ~~natural~~microgrid ~~gas~~hybrid systems, ~~and~~as ~~operate~~a atsource ~~high~~of ~~temperatures~~power ~~through~~with ~~proprietary~~global ~~chemistry.~~average ~~Marine~~run-hours ~~applications~~ranging ~~could~~from ~~be scalable for divergent load requirements and applications such as powering the entire propulsion system or~~2,920 ~~alternatively, providing auxiliary power~~ to a8,760 ~~differently powered primary propulsion system~~annually. ~~Marine~~Advent fuel ~~cell~~cells also ~~usage~~fit ~~could~~well ~~offer~~in ~~long~~industrial ~~range~~facilities, ~~and a fast refill; unlike battery power~~hospitals, and ~~longer routes and larger vessels can be powered by fuel cells as compared to batteries. In addition~~hotels, ~~fuel cells can be used in a hybrid structure in conjunction~~ with ~~battery~~backup ~~power.~~systems Weaveraging ~~are~~200 ~~planning our initial focus on applications for auxiliary marine power, and then plans~~ to ~~focus~~800 onrun ~~vessels’~~hours ~~main power~~annually.

~~We have been issued, acquired, licensed, or applied for~~Business approximately 190 international and United States patents, with a concentration in membranes, electrodes, and MEAs, which support its product offerings. In the MEA sector, our products include two existing membrane technologies: “TPS®”, which we have exclusive rights to use and was obtained Strategy

55Our growth strategy is focused on targeting the following four sectors:

~~TABLE~~● OFThe ~~CONTENTS~~stationary off-grid market is expected to be a growing market.

through patents filed by its founders and technical staff, and “PBI” technology, of which we are a selective licensee, and provides exclusive rights to us for commercial sale of MEAs using PBI technology. Leveraging our membrane technologies, we also have intellectual property for lightweight stacks made through advances in bipolar plate materials, which supports water-cooled systems. This results in a simpler and more compact balance-of-plant design. Our own investments in developing leading next-generation fuel cell technology are supported by being able to leverage the research and development efforts of its strategic partners. We are planning next generation prototypes for fuel stacks as soon as 2022, with pilot production as soon as 2023 and mass production as soon as 2024.76

~~Our~~Table ~~rights to commercialize the next-generation HT-PEM materials technology from the DoE L’Innovator Program also includes rights to a portfolio~~ of patents supporting this advanced technology. We were selected through a highly competitive bidding process by virtue of our management team’s track record in taking laboratory inventions and processes through to a fully-scaled and manufactured product. We expect that this technology will reduce production costs of its MEAs significantly through a 3-fold increase in power output per unit area of membrane, and will provide longer operating lifetime and a wider temperature operating range as well as substantially lower platinum content. We expect these advantages will enable us to reduce the cost to end-users of fuel cells and encourage a wider market adoption. We anticipate commercialization and mass manufacture of this product by 2022. This and other partnerships, joint ventures, and joint development agreements, including with DoE, NASA (through Advent’s affiliation with Northeastern University) and the European Space Agency, are expected to assist Advent in the mobility and off-grid power markets.Contents

~~Our~~● ~~products~~The and technology are currently being used in the marketplace to generate electricity for commercial applications, and we are developing partnerships with Tier 1 suppliers, OEMs, and system integrators to further drive commercial adoption and use in an increasing number of applications and end markets. To date, more than 300,000 TPS® and PBI MEAs have been sold (by us and others) for use in defense, microlarge-~~combined~~scale ~~heat and power (µCHP) systems, battery range extenders for~~ fuel cell ~~battery~~systems ~~hybrid~~market ~~vehicles, remote~~ (power ~~for telecom and auxiliary power in remote locations~~generation, ~~demonstrating~~data ~~strong~~centers ~~early-stage adoption of our existing product line. To date, we have shipped thousands of systems for defense, off-grid~~ and ~~remote/portable~~ power ~~markets~~to gas).

As● ~~our~~The ~~business ramps up to mass~~human-~~production,~~portable ~~we plan to pursue a revenue model that includes engineering fees~~defense, MEA sales and hardware-technology licensing fees through the life of product development. Our customer relationship is split into two phases: 1) partner with OEMs to co-develop customized fuel cell systems based on our MEAssurveillance, ~~for~~energy ~~which we earn engineering and licensing fees~~infrastructure, and 2)leisure ~~produce~~market ~~and~~based ~~sell proprietary MEAs directly to OEMs while earning licensing fees~~ on ~~fuel cells produced by customers using~~ our ~~technology.~~innovative WeHoney ~~expect~~Badger ~~high-margin licensing fees to become a larger component of our revenue mix over time as our customers scale to mass manufacturing of fuel cells and other~~ products.

We● ~~were~~The ~~founded~~development ~~and are managed by a team~~ of ~~world~~next-~~class electrochemists,~~generation ~~material~~MEA ~~scientists,~~ and fuel cell ~~specialists~~solutions with significant industry and manufacturing expertise. We have received numerous R&D funds from the DoE and the European Union and are considered a pioneer with years of experience in clean energy technology innovation. We have our headquarters in Boston, Massachusetts and our operations in other Massachusetts locations, as well as in California, Greece, Germany, Denmark, and the Philippines. In 2022, We will open a facility in Charlestown, Massachusetts offering research and development facilities and additional production capacity. For additional capacity, we intend to utilize existing U.S.-based toll-manufacturing for the ~~membrane~~mobility ~~and electrode production to scale-up its production levels without significant capital expenditure~~market. ~~Our Patras, Greece based production of membranes, electrodes, and MEAs benefits from labor cost and skill availability advantages.~~

WeOur approach extends beyond direct sales; we actively supply our membrane electrode assemblies (MEAs) to other fuel cell manufacturers, and we intend to ~~direct~~supply core technology through technology transfer agreements to OEMs. This serves as a cornerstone for our expansion plans, focusing on scaling up through the ~~majority~~licensing of our ~~near-term~~technology. ~~funding requirements~~Central to ~~operating~~our ~~expenses~~strategy for future growth is the emphasis on licensing agreements with large-scale manufacturers possessing market access and robust service, support, and capital ~~expenses~~expenditure ~~for~~capabilities. Through ~~product~~partnerships ~~development~~with Tier1s and ~~plan~~OEMs, we empower our collaborators to ~~make~~innovate ~~substantial~~and ~~investments~~commercialize ~~over~~fuel cell systems powered by Advent’s proprietary technology on a significant scale. Our collaborators actively manage the ~~next~~entire ~~several~~value ~~years~~chain, ~~among~~including ~~others~~sales, inmarketing, and ~~new~~after-sales ~~production~~service. ~~equipment~~Until these partnerships mature and ~~warehousing,~~reach ~~systems~~the ~~assembly~~mass ~~line~~manufacturing stage, ~~MEA~~we ~~assembly~~derive revenues from major partners ~~automation~~through Joint Development Agreements, ~~aeronautical~~which ~~stacks~~are ~~and~~pivotal ~~U.S.~~in ~~facility~~financing ~~expansion~~the early stages of market-specific product development.

~~Recent~~As our ~~Acquisitions~~business ramps up to mass production, we plan to pursue a revenue model that includes fuel cell system sales, MEA sales, and hardware-technology licensing fees. Our customer relationship is split into two phases: 1) partner with OEMs to co-develop customized fuel cell systems based on our expertise in MEAs and HT-PEM fuel cell systems. During the product development phase, we earn engineering fees, and 2) once the industry and application-specific fuel cell system are qualified, we intend to license the hardware design to OEMs or Tier1s for large-scale manufacturing in exchange for license fees. In addition, we intend to manufacture and sell proprietary MEAs directly to OEMs and Tier1s. We expect high-margin licensing fees and MEA sales to become a larger component of our revenue mix over time (vs. direct fuel cell system sales) as our customers scale to mass manufacturing of fuel cells and other products.

~~Business~~We intend ~~Combination~~to offocus ~~AMCI~~future ~~Acquisition~~production ~~Corp~~activities in the USA and potentially in Western Macedonia, Greece, upon IPCEI funding approval. We have significant capacity in place when it comes to MEA manufacturing. Regarding fuel cell manufacturing, we expect to license the technology to large-scale manufacturers and ~~Advent~~selectively ~~Technologies~~manufacture it (for defense and other promising markets directly).

~~In February 2021, we closed our business combination with AMCI~~Specific ~~Acquisition~~Product ~~Corp.~~Offerings ~~The~~Under business combination has provided us with a sustainable funding base for the next phase of our expansion efforts to respond to significant and immediate market opportunities. Our shareholders opted to roll 100% of their equity and, as of the completion of the business combination, owned 54% of the pro-forma equity base.Development

56 A. Advent MEA:

~~TABLE~~The Advent OFMEA ~~CONTENTS~~(also called the “Ion Pair MEA”) allows HT-PEM fuel cells to operate between 80°C and 240°C with an optimal temperature of 160°C. The implications of high-temperature operation are:

~~UltraCell~~1. It is ideal for eFuel-based fuel cells (e-Methanol). The HT-PEM fuel cell can work with reformate gas, impure hydrogen, and eFuels, so there is no need for new infrastructure. The existing fossil liquid fuel infrastructure, with minimal changes but without the carbon footprint, can be used for shipping, powering off-grid generators, and solving the hardest mobility electrification applications where batteries are simply not enough. (Our systems require a single-stage methanol or alternative eFuel gas reformer, typically yielding approximately 70% hydrogen and 1-2% carbon monoxide, with the remaining balance being carbon dioxide. In contrast, competing systems necessitate costly multistage reformers and palladium-based purifiers to maintain carbon monoxide levels below 10-15 ppm, a requirement for the operation of LT PEM.

On2. ~~February 18,~~It ~~2021,~~enables ~~we acquired UltraCell, formerly a fuel cell division of Bren~~highly-~~Tronics,~~efficient ~~Inc.~~thermal ~~Prior~~management toat the ~~acquisition,~~system ~~we had a mutually beneficial partnership~~level, ~~having~~making ~~worked~~our ~~together for several years. UltraCell is a leader in lightweight~~ fuel cells ideal for ~~the~~aviation ~~portable~~and ~~power market, including small~~heavy-~~scale~~duty ~~fuel cell~~automotive. ~~technology~~Airplanes, ~~for~~big ~~the~~trucks, ~~defense industry~~excavators, and ~~has~~most ~~sold~~heavy-duty ~~thousands~~applications offace ~~battery~~significant ~~pack~~thermal ~~charger~~management ~~systems~~challenges. ~~built~~Efficient ~~around~~heat ~~Advent~~rejection ~~MEAs~~is tonot ~~four NATO militaries~~possible, ~~including~~especially ~~those~~in areas of the ~~U.S.~~world ~~and~~that ~~the~~keep ~~U.K.~~getting ~~UltraCell~~hotter ~~systems~~every ~~have been deployed with excellent performance in stringent and challenging conditions and climates~~year. ~~UltraCell’s~~From ~~technology~~India ~~uses hydrogen or liquid fuels~~ to ~~deliver reliable power at a fraction of~~ the ~~weight~~Arizona ofdesert, ~~batteries.~~an ~~Traditional LT~~HT-PEM fuel cell ~~technology~~is ~~cannot be used in this type of remote environment fuel cell product due to~~ the ~~issues~~superior ~~with compressed high-purity hydrogen~~technology. ~~Our~~By ~~fuel~~operating ~~flexibility~~optimally ~~allows~~at ~~for~~160 ~~the use of methanol in its fuel cell application~~°C, ~~which is stable in liquid form, cheaper, and more accessible than hydrogen. With our technology powering UltraCell products like~~ the ~~“Honey~~Advent ~~Badger”,~~MEA ~~a portable fuel cell which~~ is ~~in advanced testing with~~ the ~~U.S.~~first ~~military,~~technology ~~multi-day~~to ~~military~~beat ~~missions~~the ~~that~~US ~~generally~~Department ~~required over 100 pounds~~ of ~~batteries~~ ~~can~~Energy ~~substitute~~heat arejection ~~fuel~~target ~~cell~~by ~~and~~reaching ~~methanol canister with~~ a ~~total~~ΔQ/T ~~weight~~level of ~~25 pounds~~1.03 ~~UltraCell’s~~at ~~fuel~~a ~~cell~~hot ~~innovations~~50 ~~are~~°C, ~~expected~~far tobelow ~~complement~~ the ~~development~~2025 goal of ~~our~~1.45 ~~next-generation~~set ~~lightweight~~at ~~systems~~only ~~for~~40 ~~the mobility market~~°C, ~~with~~a ~~an emphasis~~target on the ~~commercial~~current ~~drone,~~LT ~~aviation,~~PEM ~~and~~technology ~~heavy-duty~~can ~~automotive~~not ~~industries~~reach. ~~UltraCell~~By ~~produces~~running the ~~only~~MEA ~~made~~hot, inyou ~~the~~can ~~U.S.~~keep ~~NATO~~the ~~approved~~ fuel cell ~~products~~engine ~~and~~cool is one of only two manufacturers of NATO approved fuel cell products manufacturing in a NATO country. Since the acquisition, we have retained current UltraCell operations in the Livermore, California area, in parallel to its Boston operations, and ~~plan~~use tosmaller ~~continue~~radiators tofor doless ~~so, with the possibility of expansion in the future~~drag.

~~SerEnergy and FES~~ 77

OnTable ~~September 1, 2021 (CEST), we completed our acquisition (the “Fischer Acquisition”)~~ of SerEnergy and FES from F.E.R. fischer Edelstahlrohre GmbH (“Fischer”). SerEnergy and FES currently market and build standalone systems and critical fuel cell components. These products are complementary to the mobile systems produced by Advent. The Fischer Acquisition is well aligned to the “Any Fuel. Anywhere.” strategy, and is expected to accelerate our growing revenue base in fuel cell stacks and systems. The Fischer Acquisition also increases our patent and trademark portfolio with new intellectual property and increases our labor force by approximately 90 employees, many of whom are highly-skilled manufacturing and sales professionals experienced in the fuel cell industry. SerEnergy has deployed hundreds of standalone telecom remote self-maintaining power systems, including sales to Smart Communications, a leading telecommunications provider in the Philippines. These systems can operate in both high humidity and high temperature environments and offer remote monitoring. We believe that the combined HT-PEM fuel cell production capacity and operations in international markets, currently consisting of Germany, Denmark and the Philippines, will support our expansion into international customer segments, in particular the Asian and European markets.Contents

~~Specific~~3. ~~Product~~It ~~Offerings~~enables simple design as the balance of plant is much simpler (due to nO-water management issues). The Advent MEA does not use water as the conducting medium. It is based on a unique proprietary chemistry developed by Advent and our collaborators. “No water needed” means that the HT-PEM fuel cell system’s balance of plant and, thus, the design, testing, and manufacturing is much simpler. Thus the HT-PEM fuel cell can operate at extreme humidity high or low, extreme climates (temperature (-20 °C to 55 °C)), or air quality conditions (pollution, dust). All these factors have minimal or no effect on the HT-PEM fuel cell performance, but they can be life-ending for a typical LT-PEM system.

~~Honey~~B. ~~Badger: The~~Advent ~~Reformed Methanol Wearable~~ Fuel Cell Power System, or “Honey Badger” is an offering marketed by our subsidiary UltraCell. On June 7, 2021, the U.S. DoD, through the U.S. Army DEVCOM Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance and Reconnaissance (C5ISR) Center, with funding through the Project Manager Integrated Visual Augmentation System (PM IVAS), has entered into a contract with us to complete the MIL-STD certification of the cutting edge “Honey Badger”. “Honey Badger” is placed on a soldier worn plate carrier and provides on the move battery charging in the field. It has been selected by the DoD’s National Defense Center for Energy and Environment (NDCEE) to take part in its 2021 demonstration/validation program and is the only fuel cell to take part in this program. The NDCEE is a DoD program that addresses high-priority environmental, safety, occupational health, and energy technological challenges that are demonstrated and validated at active installations for military application. The product is offered at 20W and 50W power versions, and both are in testing and certification stages. Its core technology has completed successful field trials in Army Expeditionary Warrior Experiments and high-altitude tests in California’s Sierra Nevada. UltraCell’s “Honey Badger 50” (the 50W power version) fuel cell is the only fuel cell that is part of this program that supports the U.S. Army’s goal of having a technology-enabled force by 2028.Stack

~~M-ZERØ: Our~~Following ~~M-ZERØ~~the ~~line~~discontinued ofoperations ~~products are designed to generate power~~ in ~~remote~~Denmark ~~environments.~~and ~~Their~~the ~~use~~Serene ~~significantly~~product ~~reduces methane emissions where they replace older~~line, ~~less~~we ~~efficient~~have ~~technology.~~focused ~~The~~our ~~current~~efforts ~~M-ZERØ~~on ~~products are 50W and 150W systems, with systems featuring up to 400W of power expected to be released by~~ the ~~end~~development of ~~2022. We have entered into agreements to trial ten 50W systems in Canada starting in~~ the ~~third~~next-generation fuel ~~quarter~~cell ~~of 2021.~~ stack:

57The goal of this effort, which commenced in 2024 Q3 and will be ongoing, is to develop the next generation of HT-PEM fuel cells based on the Advent MEA. Performance-wise, our goal is to double the power density of the fuel cell stacks in the near future vs. the previous Serene product line (that was not based on Advent MEA) and also double the lifetime. These developments can result in a total capex reduction of approximately 3x vs. previous Serene systems, thus enabling a very attractive total cost of ownership model for almost all business cases in stationary and marine power. A further improvement target of 3x vs. previous MEAs resulting from improved Advent MEA and fuel cell stack performance can bring significant competitive advantages in the most challenging markets of Aerospace and Automotive.

~~TABLE~~The Advent OFFuel ~~CONTENTS~~Cell Stack will be in the range of 7kW-10kW multiples of which can be placed in cabinets for higher power, such as 100kW to 150 kW; however, longer term Advent is designing a 50kW block, thus enabling multi-MW installations by deploying parallel cabinets. Other features under development are associated with Advent’s proprietary edge-cooling technology, no methanol-water mix and metal bipolar plates use.

~~If the trials are successful, this could result in mass deployment of M-ZERØ systems during 2023~~C. ~~The~~Honey products, which are not expected to require extensive servicing or refueling schedules, can work throughout the year, including in extreme cold. Traditional green remote power options of solar plus battery storage do not function well in either extreme cold or in hard-to-reach areas. Widespread adoption of M-ZERØ technology at all of the wellheads in the U.S. and Canada will result in a substantial reduction of carbon dioxide emissions.Badger

~~Important~~The Reformed ~~Projects~~Methanol Wearable Fuel Cell Power System, or “Honey Badger” is an offering marketed by our subsidiary Advent Technologies LLC. On June 7, 2021, the US DoD, through the U.S. Army DEVCOM Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance, and Reconnaissance (C5ISR) Center, with funding through the Project Manager Integrated Visual Augmentation System (PM IVAS), has entered into a contract with us to complete the MIL-STD certification of ~~Common~~the ~~European~~cutting ~~Interest~~edge “Honey Badger”. “Honey Badger” is placed on a soldier-worn plate carrier and provides on-the-move battery charging in the field. It has been selected by the US DoD’s National Defense Center for Energy and Environment (NDCEE) to take part in its 2021 demonstration/validation program and is the only fuel cell to take part in this program. The NDCEE is a US DoD program that addresses high-priority environmental, safety, occupational health, and energy technological challenges that are demonstrated and validated at active installations for military application. The product is offered at 50W and 100W power versions, and both are in the testing and certification stages. Its core technology has completed successful field trials in Army Expeditionary Warrior Experiments and high-altitude tests in California’s Sierra Nevada. Advent Technologies LLC’s “~~IPCEI~~Honey Badger 50” (the 50W power version) fuel cell is the only fuel cell that is part of this program that supports the U.S. Army’s goal of having a technology-enabled force by 2028. On August 4, 2022, we announced the launch of our HB50 power system, a compact portable fuel cell system and quiet power supply for use in off-grid field applications such as military and rescue operations. The launch of Advent’s portable power system coincided with the Company’s fulfillment of its first shipment order from the U.S. Department of Defense. The HB50 power system can be fueled by biodegradable methanol, allowing near-silent generation of up to 50W of continuous power with clean emissions. Designed for covert operations, HB50 can easily power radio and satellite communications gear, remote fixed and mobile surveillance systems, laptop computers, and more general battery charging needs. HB50 is a unique technology that can save 65% of weight versus batteries over a typical 72-hour mission. The weight savings

White Dragon: White Dragon is an IPCEI proposal submitted by a consortium of Advent, Damco Energy S.A. (Copelouzos Group Company), PPC Greece, The Hellenic Gas Transmission System Operator (“DESFA”) S.A., Hellenic Petroleum, Motor Oil, Corinth Pipeworks, TAP and Terna Energy (together the “consortium”) to develop a more than €8 billion green hydrogen project in Greece to gradually replace Western Macedonia’s lignite coal power plants of and transition to clean energy production and transmission, with the ultimate goal of fully decarbonizing Greece's energy system. The project plans to use large-scale renewable electricity to produce green hydrogen by electrolysis in Western Macedonia. This hydrogen would then be stored and, through our HT-PEM fuel cells, would be expected to supply all of Greece with clean electricity, green energy, and heat. Our HT-PEM fuel cells provide a combination of both heat and electrical power, and the heat generated by the project can initially be used in conjunction with the district heating networks of Western Macedonia, and in the future in other applications that require a heating and/or cooling system, such as industrial workings, data centers and greenhouses. The White Dragon proposal also includes plans covering the transportation sector. We are the sole fuel cell development partner for the proposed project. Estimates are that the project, if approved, would continue from 2022 through 2029, produce over 200,000 tons of hydrogen per year, reduce annual carbon dioxide emissions by 11.5 million tons and create 18,000 direct jobs and almost 30,000 indirect jobs. We were informed in September 2021 that the Greek government had approved of the White Dragon proposal and it is currently pending European Union approval.78

~~Green~~Table ~~HiPo: Green HiPo is an IPCEI proposal submitted by us which will, if approved, allow us to develop, design, and manufacture fully scalable HT-PEM fuel cells for the production~~ of power and heat. Green HiPo is linked to, but independent of, the White Dragon project. It proposes to establish a production facility in Western Macedonia with a staggered production plan, starting with 15kW stacks, integration into 120kW modules, 1MW scale single units, and ultimately multi-MW fully integrated systems. Estimates are that the project, if approved, would continue from 2022 through 2029, create approximately 1,400 jobs in the Western Macedonia region and the total cost of the project could exceed €4 billion. We were informed in September 2021 that the Greek government had approved of the Green HiPo proposal and it is currently pending European Union approval.Contents

~~Intellectual~~benefit increases ~~Property~~further for longer missions. In September and December 2023, contracts totaling $2.2 million and $2.8 million, respectively, were signed with the U.S. Department of Defense. These contracts focus on integrating the Ion Pair MEA technology into HB50 and enhancing specific components/manufacturing processes. The objective is to facilitate the shift from low-prototype volume to small manufacturing volume. Advent and the US DoD plan to strengthen their collaboration by concentrating on the improved HB50 fuel cell system’s manufacturing process, aiming to achieve high-volume production capacity. Multiple applications of the HB50 are expected in the future in sectors such as robotics, agriculture, drones, emergency operations, and consumer uses. HB50’s unique design allows it to be used in soldier-worn configurations or operated inside a portable backpack or vehicle while charging batteries and powering soldier systems, while its thermal features allow it to operate within an ambient temperature range of -20°C to +55°C. Aside from its optimized compatibility with the Integrated Visual Augmentation System (“IVAS”), HB50 can also power devices such as high-frequency radios, such as the model 117G and B-GAN and StarLink terminals. HB50’s durability allows it to be easily deployed in challenging conditions and climates while supporting mission mobility for three to seven days without the need to re-supply. Since Honey Badger’s fuel cell technology can run on hydrogen or liquid fuels, the system can operate at a fraction of the weight of traditional military-grade batteries to meet the U.S. Department of Defense’s continuously evolving needs for ‘on-the-go’ electronics needs. As military adoption and use of IVAS equipment continue to evolve, highly portable lightweight power solutions like Honey Badger and HB50 will become a mission-critical necessity.

Our intellectual property portfolio covers among other things: membranes, electrodes, MEAs, and systems exploiting the unique operating characteristics of its materials. In general, our employees are party to agreements providing that all inventions, whether patented or not, made or conceived while being an Advent employee, which are related to or result from work or research that the Company performs, will remain our sole and exclusive property.

We have been issued, acquired, licensed, or applied for approximately 190 international patents (including the intellectual property from the Fischer Acquisition), the vast majority in membranes, electrodes, and MEAs, which support our product offerings. Additionally, we have approximately eighteen trademarks registered with the USPTO and various international trademark offices, with additional trademark applications pending.

Competition

The market for alternative fuel and energy storage systems is still in the early stages of growth and is characterized by well-established battery and LT-PEM products. We believe the principal competitive factors in the markets in which it operates include, but are not limited to, the size, weight, lifetime, durability, and total cost of ownership of these systems to the end-user. We believe that our HT-PEM technology competes with these other technologies across a number of new and existing applications in the alternative energy fuel market, especially in the realm of fuel flexibility and heat management. We believe the total addressable market opportunity could be over $72 billion by the year 2030.

58HT-PEM vs Diesel Gensets: In contrast to polluting diesel gensets, HT-PEM fuel cell technology offers a clean and sustainable alternative ready for immediate deployment. Its adaptability extends to operating with various hydrogen-carrying fuels available in today’s market. Diesel generators not only emit harmful pollutants but also pose a significant risk of fuel theft and contribute to noise pollution. With growing global concern over environmental issues, diesel gensets face escalating scrutiny and potential bans due to their emissions of pollutants such as NOx, SOx, and Particulate Matter (PM). Conversely, HT-PEM fuel cells operate without emitting harmful pollutants, while also generating minimal noise. This aligns seamlessly with evolving regulations aimed at reducing carbon footprints and underscores the viability of HT-PEM fuel cells as a sustainable energy solution.

~~TABLE~~HT-PEM vs OFLT-PEM: ~~CONTENTS~~HT-PEM technology operates at optimal temperatures for efficient heat rejection, maximizing overall efficiency and enabling operation in hot climate regions. In contrast, Low-Temperature Proton Exchange Membrane (LT-PEM) technology lacks rapid cooling capabilities, rendering it unsuitable for aerospace and heavy-duty truck applications. One of the key advantages of HT-PEM technology lies in its versatility in utilizing various hydrogen-carrying fuels, such as methanol and its derivatives. Methanol, being a liquid and easily transportable hydrogen carrier, is witnessing a steady increase in availability. Projections indicate the potential for significant growth, with 130 projects planning to produce 16 million metric tonnes (t) of methanol capacity by 2027 and 19.5 million t by 2028. Moreover, transporting compressed hydrogen off-grid presents economic challenges and safety risks. HT-PEM technology demonstrates resilience in extreme environments, offering a key differentiating factor. The absence of water in the fuel cell membrane simplifies the system and facilitates efficient operation in both hot and cold climates. Furthermore, HT-PEM fuel cells exhibit remarkable performance in extreme ambient temperatures and can function effectively even in highly polluted urban areas or harsh environmental conditions.

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HT-PEM vs SOFC: HT-PEM systems typically boast shorter start-up times compared to SOFCs, allowing for quicker deployment and response to power demands. SOFC systems are not suitable for backup or mobility applications as they are optimized to work continuously 24x7. Additionally, HT-PEM fuel cells tend to be more compact in size, offering greater flexibility in installation and integration into various applications. Cost-wise, HT-PEM systems often exhibit lower initial investment requirements compared to SOFCs, making them more accessible for a range of applications and markets. These distinctions underscore the unique advantages of HT-PEM technology in terms of efficiency, versatility, and affordability.

HT-PEM vs Batteries: When operating as standalone power sources, batteries are often impractical and cumbersome, particularly in off-grid scenarios where they require daily transportation back to the grid for recharging. Additionally, they incur high costs and offer limited runtime, while recharging from the grid often results in higher net emissions in most countries. At Advent, we firmly believe in the transformative potential of hybrid power solutions that merge our HT-PEM fuel cell technology with batteries. Unlike traditional methods, where batteries draw power from the grid, our approach for certain applications favors charging batteries using our fuel cells to ensure unlimited green power generation and provide a consistent power supply constrained only by the availability of fuel. Furthermore, our hybrid solution offers significant cost savings and extended runtime compared to battery-only alternatives. Moreover, it achieves remarkable emission reductions, up to 80% when utilizing biomethanol fuel and 100% with e-Methanol.

Research and Development

Our R&D projects cover the full lifecycle of fuel cells, from their actual development and optimization for use in hard-to-abate industries such as heavy-duty mobility to the effective recycling of end-of-life systems, emphasizing our commitment to sustainability. We are actively engaged in over 20 research and development initiatives across the EU and the US, which serve as pivotal pillars for our strategic advancement. These programs afford us the opportunity to collaborate closely with some of the world’s most esteemed research institutions, universities, and leading companies committed to decarbonized solutions. Through these partnerships, we continuously broaden our scope and expertise.

Employees and Human Capital Resources

Our employees are critical to our success. As of December 31, ~~2021~~2024, we had approximately ~~200~~26 employees, ~~including~~and 5 part-time, contractors ~~and employees who joined us from the recent Fischer Acquisition~~. We ~~also~~ occasionally rely on additional independent contractors to support our operations. ~~To date, we have not experienced any work stoppages and consider our relationship with our employees to be in good standing.~~ None of our employees are represented by a labor organization or are a party to any collective bargaining arrangement.

We strive ~~believe~~to ~~that~~create ~~developing~~ a ~~diverse,~~collaborative ~~equitable~~environment where our colleagues feel respected and ~~inclusive culture~~valued. isWe ~~critical~~provide toour ~~continuing~~employees towith ~~attract~~competitive compensation, opportunities for equity ownership, and ~~retain~~a ~~the~~robust ~~top~~employment ~~talent~~package, ~~necessary~~including ~~for~~health ~~our~~care, ~~long-term~~retirement ~~success~~benefits, and ~~strategy~~paid time off. WeIn ~~value~~addition, ~~diversity~~we atregularly ~~all~~interact ~~levels~~with our employees to gauge employee satisfaction and identify focus areas.

At Advent, we champion the belief that individual uniqueness enhances greatness. We ~~strive~~uphold equal opportunities for all employees. Through rigorous protocols, we continuously work to ~~create~~identify aand ~~collaborative~~eradicate ~~environment~~any ~~where~~form of harassment within our ~~colleagues feel~~organization, ~~respected~~fostering a fair and respectful ~~valued~~workplace. We ~~provide~~prioritize the value and respect of our employees, ~~with~~unequivocally ~~competitive~~condemning ~~compensation~~violence, ~~opportunities~~discrimination, ~~for~~or ~~equity~~harassment. Employees ~~ownership~~are ~~and~~encouraged ato ~~robust~~address ~~employment~~any ~~package,~~questions ~~including~~or ~~health~~concerns ~~care,~~they ~~retirement~~may have regarding their employment or benefits ~~and~~with ~~paid~~our ~~time~~Human ~~off~~Resources department. InWe ~~addition~~honor and accommodate the physical or mental limitations of qualified employees with disabilities, weenabling ~~regularly~~them to fulfill ~~interact~~their ~~with~~job responsibilities. Furthermore, our ~~employees~~compensation tostructure ~~gauge~~is ~~employee~~determined ~~satisfaction~~by ~~and~~factors ~~identify~~such ~~areas~~as ofposition, ~~focus~~education, and experience.

~~Properties~~80

WeTable ~~lease approximately 3,400 square feet~~ of offices located in Patras, Greece. The leases are set to expire on December 31, 2028. We entered into a lease dated February 5, 2021 for approximately 6,000 square feet of office space at 200 Clarendon Street, Boston, Massachusetts 02116 as the Company’s executive offices. The term of the lease is five years (unless sooner terminated as provided in the lease agreement). Through the Fischer Acquisition, we have leased from Fischer the space, comprising approximately 10,750 square feet, in which FES operates and acquired property containing approximately 8,600 square feet of SerEnergy office, production and laboratory facilities located in Aalborg, Denmark. We also assumed a lease from Fischer in Aalborg, Denmark for approximately 7,000 square meters containing meeting rooms and a warehouse used by SerEnergy, and office, workshop, and warehouse spaces in two locations in Paranaque City, Philippines totaling approximately 10,500 square meters. Through our wholly owned subsidiary, FES, we entered into a lease agreement with fischer group SE & Co. KG in Achern for approximately 1,017 square feet of office space, workspace and outdoor laboratory at 77855 Achern, Im Gewerbegebiet 7 for use by FES. We have a short-term lease in Somerville, Massachusetts for laboratory space while it builds out a dedicated leased space of approximately 21,400 square feet in the Hood Park complex in Charlestown, Massachusetts.Contents

Performance Management: We are committed to optimizing performance management within our organization. Our focus lies in nurturing strong relationships between our management team and employees, fostering a culture of mutual respect across all operational sites and facilities. We conduct formal performance evaluations annually to track progress and provide feedback. Furthermore, we actively encourage ongoing dialogue between employees and supervisors to discuss development goals and performance metrics regularly.

Talent and Training: Our employees engage in a range of inclusive training and development programs covering diverse subjects to enhance their skills and competencies. These include professional skills enhancement, human rights, ethics, health and safety in laboratory processes, and technological expertise. We also mandate standard business ethics training for all employees.

Health Safety Wellness: To safeguard the well-being of our employees across all operational sites, we rigorously uphold and surpass relevant safety and health regulations. At every location, Advent maintains strict adherence to local health and safety standards. Our commitment to employee welfare is articulated in our comprehensive Group Health and Safety Policy. Within Advent’s Employee Handbook, we delineate our existing protocols concerning health and safety matters and the oversight responsibilities of our management team.

Intellectual Property

Our intellectual property portfolio covers, among other things: membranes, electrodes, MEAs, and systems exploiting the unique operating characteristics of its materials. In general, our employees are party to agreements providing that all inventions, whether patented or not, made or conceived while being an Advent employee, which are related to or result from work or research that the Company performs, will remain our sole and exclusive property.

We have been issued, acquired, licensed, or applied for approximately 150 international and United States patents, with a concentration in membranes, electrodes, and MEAs, which support its product offerings. Leveraging our membrane and electrode technologies, we also have the intellectual property for lightweight stacks made through advances in bipolar plate materials, which support water-cooled systems. This results in a simpler and more compact balance-of-plant design. Our own investments in developing leading next-generation fuel cell technology are supported by being able to leverage the research and development efforts of its strategic partners.

Our rights to commercialize the next-generation HT-PEM materials technology from the DoE L’Innovator Program also includes rights to a portfolio of patents supporting this advanced technology. We were selected through a highly competitive bidding process by virtue of our management team’s track record in taking laboratory inventions and processes through to a fully scaled and manufactured product. We expect that this technology will reduce production costs of its MEAs significantly through a 3-fold increase in power output per unit area of the membrane and will provide a longer operating lifetime and a wider temperature operating range as well as substantially lower platinum content. We expect these advantages will enable us to reduce the cost to end-users of fuel cells and encourage wider market adoption.

Facilities

Our principal executive offices are located at 5637 La Ribera St., Suite A, Livermore, CA 94550 and our telephone number is (925) 455-9400. We maintain a website at https://www.advent.energy.

We believe that all our properties have been adequately maintained, are generally in good condition, and are suitable and adequate for our business.

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Legal Proceedings

~~We are from~~ From time to time, ~~subject~~we tomay ~~various~~become ~~claims,~~involved in various lawsuits and ~~other~~ legal ~~and administrative~~ proceedings ~~arising~~which arise in the ordinary course of business. ~~Some of these claims~~However, litigation ~~lawsuits~~is ~~and other proceedings may involve highly complex issues that are~~ subject to ~~substantial~~inherent uncertainties, and ~~could~~an adverse result in ~~damages,~~ ~~fines,~~these ~~penalties, non-monetary sanctions~~ or ~~relief.~~other ~~However,~~matters wemay doarise ~~not~~from ~~consider~~time ~~any~~to ~~such~~time ~~claims, lawsuits or proceedings~~ that ~~are currently pending, individually or in the aggregate, to be material to our business or likely to result in~~may aharm ~~material adverse effect on~~ our ~~future operating results, financial condition or cash flows~~business.

On ~~December~~ May 179, ~~2020~~2025, Chris Kaskavelis (“Kaskavelis”), a ~~purported~~former ~~shareholder~~employee ~~class~~of ~~action~~Advent ~~complaint was~~SA, filed bya ~~Dillon~~claim ~~Frey~~ against the Company’s wholly owned subsidiary in Greece, Advent SA, before the ~~Supreme~~Athens First Instance Court of(LABOR CLAIMS). A hearing is on the ~~State~~claim ofis ~~New~~scheduled for ~~York~~October 20, ~~County~~2025. ofIn ~~New~~connection ~~York~~with the claim, ~~alleging~~Kaskavelis alleges that Advent should pay him the ~~proposed~~following ~~Business~~amounts: ~~Combination~~(1) ~~with~~€107,194.90 for ~~Advent~~unpaid iswages, ~~both~~(2) ~~procedurally~~€612,206.40 ~~and~~for ~~substantively~~unpaid ~~unfair~~severance, (3) €50,000 for “moral damages” and ~~seeking~~(4) torelated ~~maintain~~court expenses stemming from the ~~action~~ lawsuit. The Company denies the Kaskavelis claims as athey ~~class~~are ~~action~~unsubstantiated and ~~enjoin~~without ~~the~~merit ~~Business~~as ~~Combination,~~he ~~among~~was terminated ~~other~~by ~~things,~~the ~~without~~Company ~~stating~~for acause ~~specific~~per ~~amount~~the terms of ~~damages.~~his ~~The~~employment ~~complaint~~agreement. ~~does~~Notwithstanding ~~not~~the ~~provide~~same, ~~detail~~and as toa ~~how~~contingency, the ~~proposed~~Company has ~~Business~~accrued ~~Combination~~for isthe ~~unfair,~~unpaid ~~either~~wages ~~procedurally~~portion ~~or substantively,~~of ~~and~~his weclaim ~~believe~~in itthe ~~has~~amount noof ~~merit~~€107,194.90 ~~On February 10~~($124,000). ~~2021,~~The aCompany ~~notice~~believes ofthat ~~dismissal~~the remainder of the ~~complaint~~Kaskavelis ~~was~~claims ~~filed~~are inwholly ~~the~~without ~~Supreme~~merit ~~Court~~and ofintends ~~the~~to ~~State~~defend ofitself ~~New~~vigorously ~~York~~in these proceedings, ~~County~~although we cannot accurately predict the ultimate outcome of ~~New~~this ~~York~~matter.

59On August 16, 2024, the Company was i

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