UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

__________________________

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): November 12, 2025

TECOGEN INC.

(Exact Name of Registrant as Specified in Charter)

Delaware

(State or Other Jurisdiction of Incorporation)


001-36103						04-3536131
(Commission File Number)						(IRS Employer Identification No.)



76 Treble Cove Road, Building 1
North Billerica, Massachusetts 01862
(Address of Principal Executive Offices and Zip Code)

(781) 466-6400

(Registrant's telephone number, including area code)

Securities registered or to be registered pursuant to Section 12(b) of the Act.


Title of each class	Trading Symbol	Name of exchange on which registered
Common Stock, $0.001 par value per share	TGEN	NYSE American, LLC

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). 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 with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Section 2 - Results of Operations and Financial Condition

Item 2.02. Results of Operations and Financial Condition.

On November 12, 2025, Tecogen Inc. (the “Company”) issued a press release with earnings commentary and supplemental information for the three and nine months ended September 30, 2025. A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 2.02 and Exhibit 99.1 to this Current Report on Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Securities Exchange Act of 1934, except as expressly set forth by specific reference in such a filing.

Section 7.01 - Regulation FD Disclosure

Item 7.01. Regulation FD Disclosure

On November 13, 2025, the Company will present the attached slides online in connection with an earnings conference call. The slides are being furnished as Exhibit 99.2 to this Current Report on Form 8-K.

The information in this Item 7.01 and Exhibit 99.2 to this Current Report on Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Securities Exchange Act of 1934, except as expressly set forth by specific reference in such a filing.

Section 9 - Financial Statements and Exhibits

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits


Exhibit			Description

99.1			Press Release, dated November 12, 2025 *
99.2			Earnings Call Presentation, dated November 13, 2025 *

*			Filed herewith.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Company has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.



	TECOGEN INC.

		By: /s/ Abinand Rangesh
November 12, 2025		Abinand Rangesh, Chief Executive Officer

TECOGEN INC. 8-K