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): September 17, 2026

Plug Power Inc.

(Exact name of registrant as specified in its charter)

Delaware	1-34392	22-3672377
(State or other jurisdiction	(Commission File	(IRS Employer
of incorporation)	Number)	Identification No.)

125 Vista Boulevard, Slingerlands, New York		12159
(Address of principal executive offices)		(Zip Code)

Registrant’s telephone number, including area code: (518) 782-7700

N/A

(Former name or former address, if changed since last report.)

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 (see General Instruction A.2. below):

¨	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))

Securities registered pursuant to 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Common Stock, par value $0.01 per share		PLUG		The Nasdaq Capital Market

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. ¨

Item 5.02

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On September 17, 2026, Dean C. Fullerton notified Plug Power Inc., a Delaware corporation (the “Company”), that he will be resigning as Chief Operating Officer of the Company, effective October 23, 2026, to accept a position at another company. Mr. Fullerton’s resignation was not due to any disagreement with the Company on any matter relating to its operations, policies, practices or otherwise known to any executive officer of the Company. Mr. Fullerton will assist with the transition of his duties to certain of the Company's Executive Vice Presidents and Vice Presidents. The Company thanks Mr. Fullerton for his contributions during his tenure and wishes him success in his future endeavors.

SIGNATURE

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

	Plug Power Inc.

Date: September 23, 2026	By:	/s/ Paul Middleton
	Name:	Paul Middleton
	Title:	Chief Financial Officer