Exhibit 10.28

RIGHT OF FIRST REFUSAL AND CO-SALE AGREEMENT

This Right of First Refusal and Co-Sale Agreement (this “Agreement”) is made as of January 26, 2026, by and among Opeongo, Inc., a Delaware corporation (the “Company”), the Investors (as defined below) and the Key Holders (as defined below).

RECITALS

WHEREAS, each Key Holder is the beneficial owner of shares of Capital Stock (as defined below), or of options to purchase Common Stock (as defined below);

WHEREAS, the Company and ASP Isotopes Inc., a Delaware corporation (the “Initial Investor”), are parties to that certain Series Seed-1 Preferred Stock Purchase Agreement, of even date herewith (the “Purchase Agreement”), pursuant to which the Initial Investor has agreed to purchase shares of Series Seed-1 Preferred Stock of the Company, par value $0.0001 per share (“Series Seed-1 Preferred Stock”); and

WHEREAS, the Key Holders and the Company desire to further induce the Initial Investor to purchase the Series Seed-1 Preferred Stock.

NOW, THEREFORE, the parties agree as follows:

1. Definitions.

1.1 “Affiliate” means, with respect to any specified Person, any other Person who, directly or indirectly, controls, is controlled by, or is under common control with such Person, including, without limitation, any general partner, managing member, officer, director or trustee of such Person, or any venture capital fund or other investment fund now or hereafter existing that is controlled by one or more general partners, managing members or investment advisers of, or shares the same management company or investment adviser with, such Person.

1.2 “Board of Directors” means the board of directors of the Company.

1.3 “Capital Stock” means (a) shares of Common Stock and Preferred Stock (whether now outstanding or hereafter issued in any context), (b) shares of Common Stock issued or issuable upon conversion of Preferred Stock and (c) shares of Common Stock issued or issuable upon exercise or conversion, as applicable, of stock options, warrants or other convertible securities of the Company, in each case now owned or subsequently acquired by any Key Holder, any Investor, or their respective successors or permitted transferees or assigns. For purposes of the number of shares of Capital Stock held by an Investor or Key Holder (or any other calculation based thereon), all shares of Preferred Stock shall be deemed to have been converted into Common Stock at the then‑applicable conversion ratio.

1.4 “Change of Control” means a transaction or series of related transactions in which a person, or a group of related persons, acquires from stockholders of the Company shares representing more than 50% of the outstanding voting power of the Company.

1.5 “Common Stock” means shares of Common Stock of the Company, $0.0001 par value per share.

1.6 “Company Notice” means written notice from the Company notifying the selling Key Holders and each Investor that the Company intends to exercise its Secondary Refusal Right as to a portion of the Transfer Stock with respect to any Proposed Key Holder Transfer.

1.7 “Deemed Liquidation Event” has the meaning ascribed to it in the Restated Certificate.

1.8 “Investor Notice” means written notice from any Investor notifying the Company and the selling Key Holder(s) that such Investor intends to exercise its Right of First Refusal as to some or all of the Transfer Stock with respect to any Proposed Key Holder Transfer.

1.9 “Investors” means the Initial Investor, each Person to whom the rights of an Investor are assigned pursuant to Section 6.9, and each Person who hereafter becomes a party to this Agreement pursuant to Section 6.11.

1.10 “Key Holders” means the persons named on Schedule B hereto, each Person to whom the rights of a Key Holder are assigned pursuant to Section 3.1, each Person who hereafter becomes a party to this Agreement pursuant to Section 6.9 or 6.17 and any one of them, as the context may require.

1.11 “Person” means any individual, corporation, partnership, trust, limited liability company, association, or other entity.

1.12 “Preferred Stock” means, collectively, all shares of Series Seed-1 Preferred Stock.

1.13 “Proposed Key Holder Transfer” means any assignment, sale, offer to sell, pledge, mortgage, hypothecation, encumbrance, disposition of or any other like transfer or encumbering of any Transfer Stock (or any interest therein) proposed by any of the Key Holders.

1.14 “Proposed Transfer Notice” means written notice from a Key Holder setting forth the terms and conditions of a Proposed Key Holder Transfer.

1.15 “Prospective Transferee” means any Person to whom a Key Holder proposes to make a Proposed Key Holder Transfer.

1.16 “Qualified Direct Listing” has the meaning ascribed to it in the Restated Certificate.

1.17 “Restated Certificate” means the Company’s Amended and Restated Certificate of Incorporation, as amended and/or restated from time to time.

1.18 “Right of Co-Sale” means the right, but not an obligation, of an Investor to participate in a Proposed Key Holder Transfer on the terms and conditions specified in the Proposed Transfer Notice.

1.19 “Right of First Refusal” means the right, but not an obligation, of each Investor, or its permitted transferees or assigns, to purchase some or all of the Transfer Stock with respect to a Proposed Key Holder Transfer on a pro rata basis (based upon the total number of shares of Capital Stock then held by all Investors), on the terms and conditions specified in the Proposed Transfer Notice.

1.20 “Sanctioned Party” means any Person: (i) organized under the laws of, ordinarily resident in, or located in a country or territory that is the subject of comprehensive Sanctions (“Restricted Countries”); (ii) 50% or more owned or controlled by the government of a Restricted Country; or (iii) (A) designated on a sanctioned parties list administered by the United States, including, without limitation, the U.S. Department of the Treasury’s Office of Foreign Assets Control’s Specially Designated Nationals and Blocked Persons List, Foreign Sanctions Evaders List, and Sectoral Sanctions Identification List (collectively, “Designated Parties”); or (B) 50% or more owned or, where relevant under applicable Sanctions, controlled, individually or in the aggregate, by one or more Designated Party, in each case only to the extent that dealings with such Person is are prohibited pursuant to applicable Sanctions.

1.21 “Sanctions” means applicable laws and regulations pertaining to trade and economic sanctions administered by the United States.

1.22 “Secondary Notice” means written notice from the Investors notifying the Company and the selling Key Holder that such Investor does not intend to exercise its Right of First Refusal as to all shares of any Transfer Stock with respect to a Proposed Key Holder Transfer, on the terms and conditions specified in the Proposed Transfer Notice.

1.23 “Secondary Refusal Right” means the right, but not an obligation, of the Company to purchase a portion of any Transfer Stock not purchased pursuant to the Right of First Refusal, on the terms and conditions specified in the Proposed Transfer Notice.

1.24 “Transfer Stock” means shares of Capital Stock owned by a Key Holder, or issued to a Key Holder after the date hereof (including, without limitation, in connection with any stock split, stock dividend, recapitalization, reorganization, or the like), but does not include any shares of Preferred Stock or of Common Stock that are issued or issuable upon conversion of Preferred Stock.

1.25 “Undersubscription Notice” means written notice from an Investor notifying the Company and the selling Key Holder that such Investor intends to exercise its option to purchase all or any portion of the Transfer Stock not purchased pursuant to the Right of First Refusal or the Secondary Refusal Right.

2. Agreement Among the Company, the Investors and the Key Holders.

2.1 Right of First Refusal.

(a) Grant. Subject to the terms of Section 3 below, each Key Holder hereby unconditionally and irrevocably grants to the Investors a Right of First Refusal to purchase all or any portion of Transfer Stock that such Key Holder may propose to include in a Proposed Key Holder Transfer, at the same price and on the same terms and conditions as those offered to the Prospective Transferee.

(b) Notice. Each Key Holder proposing to make a Proposed Key Holder Transfer must deliver a Proposed Transfer Notice to the Company and each Investor not later than forty-five (45) days prior to the consummation of such Proposed Key Holder Transfer. Such Proposed Transfer Notice shall contain the material terms and conditions (including price and form of consideration) of the Proposed Key Holder Transfer, the identity of the Prospective Transferee and the intended date of the Proposed Key Holder Transfer. To exercise its Right of First Refusal under this Section 2, an Investor must deliver an Investor Notice to the selling Key Holder and the Company within 15 days after delivery of the Proposed Transfer Notice (the “Investor Notice Period”) specifying the number of shares of Transfer Stock to be purchased by each Investor. In the event of a conflict between this Agreement and any other agreement that may have been entered into by a Key Holder with the Investors that contains a preexisting right of first refusal, the Investors and the Key Holder acknowledge and agree that the terms of this Agreement shall control and the preexisting right of first refusal shall be deemed satisfied by compliance with Section 2.1(a) and this Section 2.1(b).

(c) Grant of Secondary Refusal Right to the Company. Subject to the terms of Section 3 below, each Key Holder hereby unconditionally and irrevocably grants to the Company a Secondary Refusal Right to purchase all or any portion of the Transfer Stock not purchased by the Investors pursuant to the Right of First Refusal, as provided in this Section 2.1(c). If the Investors do not provide the Investor Notice exercising its Right of First Refusal with respect to all Transfer Stock subject to a Proposed Key Holder Transfer, the Investors must deliver a Secondary Notice to the selling Key Holder and to the Company to that effect no later than 15 days after the selling Key Holder delivers the Proposed Transfer

Notice to the Investors. To exercise its Secondary Refusal Right, the Company must deliver a Company Notice to the selling Key Holder and the Investors within ten days after the Investors’ deadline for its delivery of the Secondary Notice as provided in the preceding sentence.

(d) Undersubscription of Transfer Stock. If options to purchase have been exercised by the Investors and the Company pursuant to Section 2.1(b) and Section 2.1(c) with respect to some but not all of the Transfer Stock by the end of the ten day period specified in the last sentence of Section 2.1(c) (the “Company Notice Period”), then the Company shall, within five days after the expiration of the Company Notice Period, send written notice (the “Company Undersubscription Notice”) to those Investors who fully exercised their Right of First Refusal within the Investor Notice Period (the “Exercising Investors”). Each Exercising Investor shall, subject to the provisions of this Section 2.1(d), have an additional option to purchase all or any part of the balance of any such remaining unsubscribed shares of Transfer Stock on the terms and conditions set forth in the Proposed Transfer Notice. To exercise such option, an Exercising Investor must deliver an Undersubscription Notice to the selling Key Holder and the Company within ten days after the expiration of the Investor Notice Period. In the event there are two or more such Exercising Investors that choose to exercise the last-mentioned option for a total number of remaining shares in excess of the number available, the remaining shares available for purchase under this Section 2.1(d) shall be allocated to such Exercising Investors pro rata based on the number of shares of Transfer Stock such Exercising Investors have elected to purchase pursuant to the Right of First Refusal (without giving effect to any shares of Transfer Stock that any such Exercising Investor has elected to purchase pursuant to the Company Undersubscription Notice). If the options to purchase the remaining shares are exercised in full by the Exercising Investors, the Company shall immediately notify all of the Exercising Investors and the selling Key Holder of that fact.

(e) Consideration; Closing. If the consideration proposed to be paid for the Transfer Stock is in property, services or other non-cash consideration, the fair market value of the consideration shall be as determined in good faith by the Board of Directors and as set forth in the Investor Notice. If the Company or any Investor for any reason cannot or does not wish to pay for the Transfer Stock in the same form of non-cash consideration, the Company or such Investor may pay the cash value equivalent thereof, as determined in good faith by the Board of Directors and as set forth in the Investor Notice. The closing of the purchase of Transfer Stock by the Company and the Investors shall take place, and all payments from the Company and the Investors shall have been delivered to the selling Key Holder, by the later of (i) the date specified in the Proposed Transfer Notice as the intended date of the Proposed Key Holder Transfer; and (ii) forty-five (45) days after delivery of the Proposed Transfer Notice.

2.2 Right of Co-Sale.

(a) Exercise of Right. If any Transfer Stock subject to a Proposed Key Holder Transfer is not purchased pursuant to Section 2.1 above and thereafter is to be sold to a Prospective Transferee, each respective Investor may elect to exercise its Right of Co-Sale and participate on a pro rata basis in the Proposed Key Holder Transfer as set forth in Section 2.2(b) below and, subject to Section 2.2(d), otherwise on the same terms and conditions specified in the Proposed Transfer Notice. Each Investor who desires to exercise its Right of Co-Sale (each, a “Participating Investor”) must give the selling Key Holder written notice to that effect within fifteen (15) days after the deadline for delivery of the Secondary Notice described above, and upon giving such notice such Participating Investor shall be deemed to have effectively exercised the Right of Co-Sale.

(b) Shares Includable. Each Participating Investor may include in the Proposed Key Holder Transfer all or any part of such Participating Investor’s Capital Stock equal to the product obtained by multiplying (i) the aggregate number of shares of Transfer Stock subject to the Proposed Key Holder Transfer (excluding shares purchased by the Company or the Participating Investors pursuant to the Right

of First Refusal or the Secondary Refusal Right) by (ii) a fraction, the numerator of which is the number of shares of Capital Stock owned by such Participating Investor immediately before consummation of the Proposed Key Holder Transfer and the denominator of which is the total number of shares of Capital Stock owned, in the aggregate, by all Participating Investors immediately prior to the consummation of the Proposed Key Holder Transfer , plus the number of shares of Transfer Stock held by the selling Key Holder. To the extent one or more of the Participating Investors exercise such right of participation in accordance with the terms and conditions set forth herein, the number of shares of Transfer Stock that the selling Key Holder may sell in the Proposed Key Holder Transfer shall be correspondingly reduced.

(c) Purchase and Sale Agreement. The Participating Investors and the selling Key Holder agree that the terms and conditions of any Proposed Key Holder Transfer in accordance with this Section 2.2 will be memorialized in, and governed by, a written purchase and sale agreement with the Prospective Transferee (the “Purchase and Sale Agreement”) with customary terms and provisions for such a transaction, and the Participating Investors and the selling Key Holder further covenant and agree to enter into such Purchase and Sale Agreement as a condition precedent to any sale or other transfer in accordance with this Section 2.2.

(d) Allocation of Consideration.

(i) Subject to Section 2.2(d)(ii), the aggregate consideration payable to the Participating Investors and the selling Key Holder shall be allocated based on the number of shares of Capital Stock sold to the Prospective Transferee by each Participating Investor and the selling Key Holder as provided in Section 2.2(b), provided that if a Participating Investor wishes to sell Preferred Stock, the price set forth in the Proposed Transfer Notice shall be appropriately adjusted based on the conversion ratio of the Preferred Stock into Common Stock.

(ii) In the event that the Proposed Key Holder Transfer constitutes a Change of Control, the terms of the Purchase and Sale Agreement shall provide that the aggregate consideration from such transfer shall be allocated to the Participating Investors and the selling Key Holder in accordance with Sections 2.1 and 2.2 of Article Fourth, Part B of the Restated Certificate and, if applicable, the next sentence as if (A) such transfer were a Deemed Liquidation Event, and (B) the Capital Stock sold in accordance with the Purchase and Sale Agreement were the only Capital Stock outstanding. In the event that a portion of the aggregate consideration payable to the Participating Investor(s) and selling Key Holder is placed into escrow and/or is payable only upon satisfaction of contingencies, the Purchase and Sale Agreement shall provide that (x) the portion of such consideration that is not placed in escrow and is not subject to contingencies (the “Initial Consideration”) shall be allocated in accordance with Sections 2.1 and 2.2 of Article Fourth, Part B of the Restated Certificate as if the Initial Consideration were the only consideration payable in connection with such transfer, and (y) any additional consideration which becomes payable to the Participating Investor(s) and selling Key Holder upon release from escrow or satisfaction of such contingencies shall be allocated in accordance with Sections 2.1 and 2.2 of Article Fourth, Part B of the Restated Certificate after taking into account the previous payment of the Initial Consideration as part of the same transfer.

(e) Purchase by Selling Key Holder; Deliveries. Notwithstanding Section 2.2(c) above, if any Prospective Transferee(s) refuse(s) to purchase securities subject to the Right of Co-Sale from any Participating Investor or Investors or upon the failure to negotiate in good faith a Purchase and Sale Agreement reasonably satisfactory to the Participating Investors, no Key Holder may sell any Transfer Stock to such Prospective Transferee(s) unless and until, simultaneously with such sale, such Key Holder purchases all securities subject to the Right of Co-Sale from such Participating Investor or Investors on the same terms and conditions (including the proposed purchase price) as set forth in the Proposed Transfer Notice and as provided in Section 2.2(d)(i); provided, however, if such sale constitutes a Change of Control,

the portion of the aggregate consideration paid by the selling Key Holder to such Participating Investor or Investors shall be made in accordance with the first sentence of Section 2.2(d)(ii). In connection with such purchase by the selling Key Holder, such Participating Investor or Investors shall deliver to the selling Key Holder any stock certificate or certificates, properly endorsed for transfer, representing the Capital Stock being purchased by the selling Key Holder (or request that the Company effect such transfer in the name of the selling Key Holder). Any such shares transferred to the selling Key Holder will be transferred to the Prospective Transferee against payment therefor in consummation of the sale of the Transfer Stock pursuant to the terms and conditions specified in the Proposed Transfer Notice, and the selling Key Holder shall concurrently therewith remit or direct payment to each such Participating Investor the portion of the aggregate consideration to which each such Participating Investor is entitled by reason of its participation in such sale as provided in this Section 2.2(e).

(f) Additional Compliance. If any Proposed Key Holder Transfer is not consummated within forty-five (45) days after receipt of the Proposed Transfer Notice by the Company, the Key Holders proposing the Proposed Key Holder Transfer may not sell any Transfer Stock unless they first comply in full with each provision of this Section 2. The exercise or election not to exercise any right by any Investor hereunder shall not adversely affect its right to participate in any other sales of Transfer Stock subject to this Section 2.2.

2.3 Effect of Failure to Comply.

(a) Transfer Void; Equitable Relief. Any Proposed Key Holder Transfer not made in compliance with the requirements of this Agreement shall be null and void ab initio, shall not be recorded on the books of the Company or its transfer agent and shall not be recognized by the Company. Each party hereto acknowledges and agrees that any breach of this Agreement would result in substantial harm to the other parties hereto for which monetary damages alone could not adequately compensate. Therefore, the parties hereto unconditionally and irrevocably agree that any non-breaching party hereto shall be entitled to seek protective orders, injunctive relief and other remedies available at law or in equity (including, without limitation, seeking specific performance or the rescission of purchases, sales and other transfers of Transfer Stock not made in strict compliance with this Agreement).

(b) Violation of First Refusal Right. If any Key Holder becomes obligated to sell any Transfer Stock to the Company or any Investor under this Agreement and fails to deliver such Transfer Stock in accordance with the terms of this Agreement, the Company and/or such Investor may, at its option, in addition to all other remedies it may have, send to such Key Holder the purchase price for such Transfer Stock as is herein specified and transfer to the name of the Company or such Investor (or request that the Company effect such transfer in the name of an Investor) on the Company’s books any certificates, instruments, or book entry representing the Transfer Stock to be sold.

(c) Violation of Co-Sale Right. If any Key Holder purports to sell any Transfer Stock in contravention of the Right of Co-Sale (a “Prohibited Transfer”), each Participating Investor who desires to exercise its Right of Co-Sale under Section 2.2 may, in addition to such remedies as may be available by law, in equity or hereunder, require such Key Holder to purchase from such Participating Investor the type and number of shares of Capital Stock that such Participating Investor would have been entitled to sell to the Prospective Transferee had the Prohibited Transfer been effected in compliance with the terms of Section 2.2. The sale will be made on the same terms, including, without limitation, as provided in Section 2.2(d)(i) and the first sentence of Section 2.2(d)(ii), as applicable, and subject to the same conditions as would have applied had the Key Holder not made the Prohibited Transfer, except that the sale (including, without limitation, the delivery of the purchase price) must be made within ninety (90) days after the Participating Investor learns of the Prohibited Transfer, as opposed to the timeframe proscribed in Section 2.2. Such Key Holder shall also reimburse each Participating Investor for any and all reasonable and

documented out-of-pocket fees and expenses, including reasonable legal fees and expenses, incurred pursuant to the exercise or the attempted exercise of the Participating Investor’s rights under Section 2.2.

3. Exempt Transfers.

3.1 Exempt Transfers. Notwithstanding the foregoing or anything to the contrary herein, the provisions of Sections 2.1 and 2.2 shall not apply:(a) in the case of a Key Holder that is an entity, upon a transfer by such Key Holder to its stockholders, members, partners or other equity holders;

(b) to a repurchase of Transfer Stock from a Key Holder by the Company at a price no greater than that originally paid by such Key Holder for such Transfer Stock and pursuant to an agreement containing vesting and/or repurchase provisions approved by a majority of the Board of Directors;

(c) in the case of a Key Holder that is a natural person, upon a transfer of Transfer Stock by such Key Holder made for bona fide estate planning purposes, either during such person’s lifetime or on death by will or intestacy to such person’s spouse, including any life partner or similar statutorily-recognized domestic partner, child (natural or adopted), or any other direct lineal descendant of such Key Holder (or such person’s spouse, including any life partner or similar statutorily-recognized domestic partner) (all of the foregoing collectively referred to as “family members”), or any other relative/person approved by a majority of the disinterested members of the Board of Directors, or any custodian or trustee of any trust, partnership, limited liability company or other corporate entity for the benefit of, or the ownership interests of which are owned wholly by such Key Holder or any such family members, including, without limitation, any trustee (whether individual or corporate) appointed pursuant to Israeli law (including the Israeli Income Tax Ordinance or Israeli Succession Law) for bona fide estate, inheritance or tax planning purposes;

(d) upon a transfer of Transfer Stock by such Key Holder made to a charitable organization for bona fide charitable purposes, either during such person’s lifetime or on death by will or intestacy; or

(e) in the case of a Key Holder that is a trust, upon a transfer of Transfer Stock to the beneficiaries of that trust and to any substitute trust.

provided that, the Key Holder shall deliver prior written notice to the Company and the Investors of such pledge, gift or transfer, such shares of Transfer Stock shall at all times remain subject to the terms and restrictions set forth in this Agreement, and such transferee shall, as a condition to such Transfer, deliver a counterpart signature page to this Agreement as confirmation that such transferee shall be bound by all the terms and conditions of this Agreement as a Key Holder (but only with respect to the securities so transferred to the transferee), including the obligations of a Key Holder with respect to Proposed Key Holder Transfers of such Transfer Stock pursuant to Section 2; and provided further in the case of any transfer pursuant to clause (a), (c), (d) or (e) above, that such transfer is made pursuant to a transaction in which there is no consideration actually paid for such transfer.

3.2 Exempted Offerings. Notwithstanding the foregoing or anything to the contrary herein, the provisions of Section 2 shall not apply to the sale of any Transfer Stock: (a) to the public in an offering pursuant to an effective registration statement under the Securities Act of 1933, as amended (a “Public Offering”); or (b) pursuant to a Deemed Liquidation Event.

4. Legend. Each certificate, instrument, or book entry representing shares of Transfer Stock held by the Key Holders or issued to any permitted transferee in connection with a transfer permitted by Section 3.1 hereof shall be notated with the following legend:

THE SALE, PLEDGE, HYPOTHECATION, OR TRANSFER OF THE SECURITIES REPRESENTED HEREBY IS SUBJECT TO, AND IN CERTAIN CASES PROHIBITED BY, THE TERMS AND CONDITIONS OF A CERTAIN RIGHT OF FIRST REFUSAL AND CO-SALE AGREEMENT BY AND AMONG THE STOCKHOLDER, THE CORPORATION AND CERTAIN OTHER HOLDERS OF STOCK OF THE CORPORATION. COPIES OF SUCH AGREEMENT MAY BE OBTAINED UPON WRITTEN REQUEST TO THE SECRETARY OF THE CORPORATION.

Each Key Holder agrees that the Company may instruct its transfer agent to impose transfer restrictions on the shares notated with the legend referred to in this Section 4 to enforce the provisions of this Agreement, and the Company agrees to promptly do so. The legend shall be removed upon termination of this Agreement at the request of the holder.

5. Lock-Up.

5.1 Agreement to Lock-Up. Each Key Holder hereby agrees that it will not, without the prior written consent of the managing underwriter, during the period commencing on the date of the final prospectus relating to a Public Offering, the registration by the Company of shares of its Common Stock or any other equity securities on a registration statement (other than a Form S-8), and ending on the date specified by the managing underwriter or the Company, as applicable (such period not to exceed 180 days, or such other period as may be requested by the Company or an underwriter to accommodate regulatory restrictions on (1) the publication or other distribution of research reports and (2) analyst recommendations and opinions, including, but not limited to, the restrictions contained in applicable FINRA rules, or any successor provisions or amendments thereto), (a) lend; offer; pledge; sell; contract to sell; sell any option or contract to purchase; purchase any option or contract to sell; grant any option, right, or warrant to purchase; or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock (or other equity securities of the Company) or any securities convertible into or exercisable or exchangeable (directly or indirectly) for such Common Stock (or other equity securities) held or (b) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Capital Stock, whether any such transaction described in clause (a) or (b) above is to be settled by delivery of Capital Stock or other securities, in cash or otherwise. The foregoing provisions of this Section 5 shall not apply to the sale of any shares to an underwriter pursuant to an underwriting agreement or to the establishment of a trading plan pursuant to Rule 10b5-1, provided that such plan does not permit transfers during the restricted period. The Company’s underwriters are intended third‑party beneficiaries of this Section 5 and shall have the right, power and authority to enforce the provisions hereof as though they were a party hereto. Each Key Holder further agrees to execute such agreements as may be reasonably requested by the underwriters that are consistent with this Section 5 or that are necessary to give further effect thereto. In the event a Key Holder is or becomes party to a lock-up or market standoff agreement with the Company or any third party beneficiary of this Section 5.1 that contains terms that are more restrictive to the Key Holder, the Key Holder agrees that the Key Holder shall be subject to the more restrictive terms and compliance therewith shall be deemed compliance herewith.

5.2 Stop Transfer Instructions. In order to enforce the foregoing covenant, the Company may impose stop-transfer instructions with respect to the shares of Capital Stock of each Key Holder (and transferees and assignees thereof) until the end of such restricted period.

5.3 Survival. Unless and only to the extent otherwise superseded by an underwriting agreement entered into in connection with the underwritten Public Offering, the obligations of the Key

Holders under this Section 5 shall survive the termination of this Agreement or any provision(s) of this Agreement.6. Miscellaneous.

6.1 Term. This Agreement shall automatically terminate upon the earlier of (a) immediately prior to the consummation of the Company’s initial Public Offering or Qualified Direct Listing, as applicable, and (b) the consummation of a Deemed Liquidation Event in which the consideration received by the Investors in such Deemed Liquidation Event is in the form of cash and/or publicly traded securities, or if the Investors receive substantially similar rights.

6.2 Stock Split. All references to numbers of shares in this Agreement shall be appropriately adjusted to reflect any stock dividend, split, combination or other recapitalization affecting the Capital Stock occurring after the date of this Agreement.

6.3 Ownership. Each Key Holder represents and warrants that such Key Holder is the sole legal and beneficial owner of the shares of Transfer Stock subject to this Agreement and that no other person or entity has any interest in such shares (other than a community property interest as to which the holder thereof has acknowledged and agreed in writing to the restrictions and obligations hereunder).

6.4 Dispute Resolution.

(a) The parties (i) hereby irrevocably and unconditionally submit to the jurisdiction of the state courts of Delaware and to the jurisdiction of the United States District Court for the District of Delaware for the purpose of any suit, action or other proceeding arising out of or based upon this Agreement, (ii) agree not to commence any suit, action or other proceeding arising out of or based upon this Agreement except in the state courts of Delaware or the United States District Court for the District of Delaware, and (iii) hereby waive, and agree not to assert, by way of motion, as a defense, or otherwise, in any such suit, action or proceeding, any claim that it is not subject personally to the jurisdiction of the above-named courts, that its property is exempt or immune from attachment or execution, that the suit, action or proceeding is brought in an inconvenient forum, that the venue of the suit, action or proceeding is improper or that this Agreement or the subject matter hereof may not be enforced in or by such court.

(b) Each of the parties to this Agreement consents to personal jurisdiction for any equitable action sought in the U.S. District Court for the District of Delaware or any court of the State of Delaware having subject matter jurisdiction.

(c) Waiver of Jury Trial: EACH PARTY HEREBY WAIVES ITS RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS AGREEMENT, THE OTHER TRANSACTION AGREEMENTS, THE SECURITIES OR THE SUBJECT MATTER HEREOF OR THEREOF. THE SCOPE OF THIS WAIVER IS INTENDED TO BE ALL-ENCOMPASSING OF ANY AND ALL DISPUTES THAT MAY BE FILED IN ANY COURT AND THAT RELATE TO THE SUBJECT MATTER OF THIS TRANSACTION, INCLUDING, WITHOUT LIMITATION, CONTRACT CLAIMS, TORT CLAIMS (INCLUDING NEGLIGENCE), BREACH OF DUTY CLAIMS, AND ALL OTHER COMMON LAW AND STATUTORY CLAIMS. THIS SECTION HAS BEEN FULLY DISCUSSED BY EACH OF THE PARTIES HERETO AND THESE PROVISIONS WILL NOT BE SUBJECT TO ANY EXCEPTIONS. EACH PARTY HERETO HEREBY FURTHER WARRANTS AND REPRESENTS THAT SUCH PARTY HAS REVIEWED THIS WAIVER WITH ITS LEGAL COUNSEL, AND THAT SUCH PARTY KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL COUNSEL.

6.5 Notices.

(a) All notices and other communications given or made pursuant to this Agreement shall be in writing (including email as permitted in this Agreement) and shall be deemed effectively given upon the earlier of actual receipt or: (i) personal delivery to the party to be notified; (ii) when sent, if sent by email during normal business hours of the recipient, and if not sent during normal business hours, then on the recipient’s next business day; (iii) five days after having been sent by registered or certified mail, return receipt requested, postage prepaid; or (iv) one business day after deposit with a nationally recognized overnight courier, freight prepaid, specifying next business day delivery, with written verification of receipt. All communications shall be sent to the respective parties at their address as set forth on Schedule A or Schedule B hereof, as the case may be, or (as to the Company) to the address set forth on the signature page hereto, or in any case to such email address or address as subsequently modified by written notice given in accordance with this Section 6.5. If notice is given to the Company, a copy (which copy shall not constitute notice) shall also be sent to Morgan, Lewis & Bockius LLP, One Federal Street, Boston, Massachusetts 02110-1726, Attention: Michael K. Barron, Esq., email: [email protected], and if notice is given to any Investor, a copy (which copy shall not constitute notice) shall also be given to any “cc” addressed noted on Schedule A for such Investor.

(b) Consent to Electronic Notice. Each party to this Agreement consents to the delivery of any stockholder notice pursuant to the Delaware General Corporation Law (the “DGCL”), as amended or superseded from time to time, by email pursuant to Section 232 of the DGCL (or any successor thereto) at the email address set forth below such party’s name on the Schedules hereto, as updated from time to time by notice to the Company, or as on the books of the Company. To the extent that any notice given by means of email is returned or undeliverable for any reason, the foregoing consent shall be deemed to have been revoked until a new or corrected email address has been provided, and such attempted electronic notice shall be ineffective and deemed to not have been given. Each party to this Agreement agrees to promptly notify the Company of any change in its email address, and that failure to do so shall not affect the foregoing.

6.6 Entire Agreement. This Agreement (including the Exhibits and Schedules hereto) together with the other Transaction Agreements (as defined in the Purchase Agreement) constitute the full and entire understanding and agreement among the parties with respect to the subject matter hereof, and any other written or oral agreement relating to the subject matter hereof existing between or among any of the parties are expressly canceled.

6.7 Delays or Omissions. No delay or omission to exercise any right, power or remedy accruing to any party under this Agreement, upon any breach or default of any other party under this Agreement, shall impair any such right, power or remedy of such non-breaching or non-defaulting party nor shall it be construed to be a waiver of any such breach or default, or an acquiescence therein, or of or in any similar breach or default thereafter occurring; nor shall any waiver of any single breach or default be deemed a waiver of any other breach or default theretofore or thereafter occurring. Any waiver, permit, consent or approval of any kind or character on the part of any party of any breach or default under this Agreement, or any waiver on the part of any party of any provisions or conditions of this Agreement, must be in writing and shall be effective only to the extent specifically set forth in such writing. All remedies, either under this Agreement or by law or otherwise afforded to any party, shall be cumulative and not alternative.

6.8 Amendment; Waiver and Termination.

(a) This Agreement may be amended, modified or terminated (other than pursuant to Section 6.1 above) and the observance of any term hereof may be waived (either generally or in a particular instance and either retroactively or prospectively) only by a written instrument executed by (i) the

Company, (ii) the Key Holders holding a majority of the shares of Transfer Stock then held by all of the Key Holders, and (iii) the holders of at least a majority of the shares of Preferred Stock then held by the Investors (voting as a single separate class and on an as-converted basis); provided that the Company may in its sole discretion waive compliance with any provision of this Agreement if observance of the terms would cause the Company or any Investor to be in violation of applicable Sanctions.

(b) Any amendment, modification, termination or waiver effected in accordance with this Section 6.8 shall be binding upon the Company, the Investors, the Key Holders and all of their respective successors and permitted assigns whether or not such party, assignee or other shareholder entered into or approved such amendment, modification, termination or waiver.

(i) this Agreement may not be amended, modified or terminated and the observance of any term hereunder may not be waived with respect to any Investor or Key Holder without the written consent of such Investor or Key Holder unless such amendment, modification, termination or waiver applies to all Investors and Key Holders, respectively, in the same fashion; provided, however, if, after giving effect to any waiver of Section 2 with respect to a particular transaction, a waiving Investor in fact purchases or sells securities in such transaction (a “Participating Investor”), the aforementioned waiver shall be deemed to apply to any Investor only if that Investor has been provided the opportunity to purchase or sell a proportional number of the securities in such transaction based on relative participation of all Participating Investors);

(ii) no consent of any Key Holder shall be required for a waiver of the applicability of the rights provided in Section 2 of this Agreement as to any specific Proposed Key Holder Transfer; and

(iii) the consent of the Key Holders shall not be required for any amendment, modification, termination or waiver if such amendment, modification, termination or waiver does not affect the rights and obligations set forth in this Agreement of the Key Holders,

(d) Section 2.2, Section 2.3(c), Section 5 and this Section 6.8(d) may not be amended, modified or terminated and the observance of any term hereunder may not be waived without the written consent of Key Holders holding a majority of the shares of Transfer Stock then held by all of the Key Holders.

(e) The Company shall give prompt written notice of any amendment, modification or termination hereof or waiver hereunder to any party hereto that did not consent in writing to such amendment, modification, termination or waiver; provided that the failure to provide such notice shall not invalidate any amendment, modification, termination or waiver hereunder; and provided further, for clarity, that no such notice shall be required to be given to any Key Holder for a waiver of the applicability of the rights provided in Section 2 of this Agreement as to any specific Proposed Key Holder Transfer that does not involve any Transfer Stock held by such Key Holder.

(f) No waivers of or exceptions to any term, condition or provision of this Agreement, in any one or more instances, shall be deemed to be, or construed as, a further or continuing waiver of any such term, condition or provision.

(g) Any amendment, modification, termination, or waiver effected in accordance with this Section 6.8 shall be binding on all parties hereto, regardless of whether any such party has consented thereto or received notice thereof.

6.9 Assignment of Rights.

(a) The terms and conditions of this Agreement shall inure to the benefit of and be binding upon the respective successors and permitted assigns of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors and permitted assigns any rights, remedies, obligations, or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement.

(b) Any successor or permitted assignee of any Key Holder, including any Prospective Transferee who purchases shares of Transfer Stock in accordance with the terms hereof, shall deliver to the Company and the Investors, as a condition to any transfer or assignment, a counterpart signature page hereto pursuant to which such successor or permitted assignee shall confirm their agreement to be subject to and bound by all of the provisions set forth in this Agreement that were applicable to the predecessor or assignor of such successor or permitted assignee.

(c) The rights of the Investors hereunder are not assignable without the Company’s written consent (which shall not be unreasonably withheld, delayed or conditioned), except (i) by an Investor to any Affiliate, or (ii) to an assignee or transferee who acquires at least 871,388 shares of Capital Stock (as adjusted for any stock combination, stock split, stock dividend, recapitalization or other similar transaction), it being acknowledged and agreed that any such assignment, including an assignment contemplated by the preceding clauses (i) or (ii) shall be subject to and conditioned upon any such assignee’s delivery to the Company and the other Investors of a counterpart signature page hereto pursuant to which such assignee shall confirm their agreement to be subject to and bound by all of the provisions set forth in this Agreement that were applicable to the assignor of such assignee.

(d) Except in connection with an assignment by the Company by operation of law to the acquirer of the Company, the rights and obligations of the Company hereunder may not be assigned under any circumstances.

6.10 Severability. The invalidity or unenforceability of any provision hereof shall in no way affect the validity or enforceability of any other provision.

6.11 Additional Investors. Notwithstanding anything to the contrary contained herein, if the Company issues additional shares of the Company’s Preferred Stock after the date hereof, any purchaser of such shares of Preferred Stock may become a party to this Agreement by executing and delivering a counterpart signature page to this Agreement and thereafter shall be deemed an “Investor” for all purposes hereunder.

6.12 Governing Law. This Agreement and all claims, causes of action, actions, suits, and proceedings (whether in contract, tort or statute) that may be based upon, arise out of or relate to this Agreement, or the negotiation, execution or performance of this Agreement (including any claim, cause of action, action, suit, or proceeding based upon, arising out of, or related to any transaction contemplated by this Agreement, any representation or warranty made in or in connection with this Agreement, or as an inducement to enter into this Agreement) (a “Dispute”), shall be governed by, and enforced in accordance with, the internal law of the State of Delaware, including its statutes of limitations, without regard to conflict of law principles that would result in the application of any law other than the law of the State of Delaware.

6.13 Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.

6.14 Counterparts. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

Counterparts may be delivered via email (including pdf or any electronic signature complying with the U.S. federal ESIGN Act of 2000, e.g., www.docusign.com) or other transmission method and any counterpart so delivered shall be deemed to have been duly and validly delivered and be valid and effective for all purposes.

6.15 Aggregation of Stock. All shares of Capital Stock held or acquired by Affiliates shall be aggregated together for the purpose of determining the availability of any rights under this Agreement and such Affiliates may apportion such rights as among themselves in any manner they deem appropriate.

6.16 Specific Performance. In addition to any and all other remedies that may be available at law in the event of any breach of this Agreement, each Investor shall be entitled to specific performance of the agreements and obligations of the Company and the Key Holders hereunder and to such other injunction or other equitable relief as may be granted by a court of competent jurisdiction.

6.17 Additional Key Holders. In the event that after the date of this Agreement, the Company issues shares of Common Stock, or options to purchase Common Stock, to any employee or consultant, which shares or options would collectively constitute with respect to such employee or consultant (taking into account all shares of Common Stock, options and other purchase rights held by such employee or consultant) 1% or more of the Company’s then outstanding Common Stock (treating for this purpose all shares of Common Stock issuable upon exercise of or conversion of outstanding options, warrants or convertible securities, as if exercised or converted), the Company shall, as a condition to such issuance, cause such employee or consultant to execute a counterpart signature page hereto as a Key Holder, and such person shall thereby be bound by, and subject to, all the terms and provisions of this Agreement applicable to a Key Holder.

6.18 Sanctions. For the avoidance of doubt, at any time that a Person is or becomes a Sanctioned Party, all rights granted to the Person under this Agreement, including, without limitation, any right to purchase any Capital Stock, will be immediately suspended for so long as such Person is a Sanctioned Party or until authorization is issued by a relevant government authority as required by applicable Sanctions.

6.19 Costs of Enforcement. Each party will bear its own costs in respect of any disputes arising under this Agreement. The prevailing party shall be entitled to reasonable attorney’s fees, costs, and necessary disbursements in addition to any other relief to which such party may be entitled.

[Signature Pages Follow]

IN WITNESS WHEREOF, the parties have executed this Right of First Refusal and Co-Sale Agreement as of the date first written above.


COMPANY:

OPEONGO, INC.

By:	/s/ David Baram
Name:	David Baram
Title:	Chief Executive Officer

     Address:

     Opeongo, Inc.
2332 Galiano Street
Coral Gables, FL 33134
Attention: David Baram
Email: [email protected]

    

ASP Isotopes Inc. 10-Q