8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) ofthe Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):February 11, 2026

Plug Power Inc.

(Exact name of registrant as specified in itscharter)

(518) 782-7700

Registrant’s telephone number, includingarea code:

N/A

(Former name or former address, if changedsince 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):

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

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. ¨

As previously announced, Plug Power Inc. (the “Company”) convened its special meeting of stockholders (the “Special Meeting”) on January 29, 2026 and adjourned the Special Meeting to February 5, 2026. On February 5, 2026, the Special Meeting was further adjourned to February 17, 2026 at 4:00 p.m. Eastern Time to allow the Company to continue soliciting additional proxies with respect to Proposals 1 and 2 described in the Company’s definitive proxy statement filed with the Securities and Exchange Commission on December 12, 2025.

The Company has determined to accelerate the reconvened Special Meeting. On February 11, 2026, the Company issued a press release announcing the acceleration of the reconvened Special Meeting from February 17, 2026 to February 12, 2026 at 4:00 p.m. Eastern Time. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The Company’s stockholders of record as of December 12, 205, the record date for the Special Meeting, are entitled to attend and vote at the reconvened Special Meeting using the same process in place for the originally scheduled Special Meeting, the details of which are set forth in the Company’s definitive proxy statement.

No changes have been made to the proposals to be voted on at the Special Meeting, and no new proposals will be presented at the reconvened Special Meeting. The reconvened Special Meeting will be held solely to conduct the vote on Proposals 1 and 2 described in the definitive proxy statement.

(d) Exhibits.

SIGNATURES

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.

Exhibit 99.1

MEDIA ADVISORY

For Immediate Release

Plug Power Accelerates Reconvened Session of Special Meeting ofStockholders to Thursday, February 12, 2026

Meeting Date Moved Earlier; Stockholders Encouraged to Vote andParticipate Virtually

Plug Power Inc. (NASDAQ: PLUG), a global leader in comprehensive hydrogen solutions for the hydrogen economy, today announced that it is accelerating the reconvened session of its Special Meeting of Stockholders. The reconvened Special Meeting was previously scheduled to be held on February 17, 2026, at 4:00 p.m. Eastern Time. The Company has determined to move the reconvened Special Meeting to Thursday, February 12, 2026, at 4:00 p.m. Eastern Time. The meeting will be held in a virtual format.

Stockholders of record as of December 12, 2025, remain eligible to participate.

Join the call:

Stockholders attending the virtual meeting will be able to vote and submit questions in real time. Participants should have their 16-digit control number from their proxy materials to access the meeting.

Important Additional Information and Where to Find It

Plug has filed a definitive proxy statement and other relevant documents with the U.S. Securities and Exchange Commission (“SEC”) in connection with the Special Meeting. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT AND OTHER RELEVANT DOCUMENTS FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY because they contain important information about the matters to be voted on at the Special Meeting. Stockholders may obtain copies of these documents free of charge at the SEC’s website at www.sec.gov or on Plug’s website at www.plugpower.com.

Participants in the Solicitation

The Company and its directors and executive officers may be deemed to be participants in the solicitation of proxies from the Company’s stockholders in connection with the Special Meeting. Information about the Company’s directors and executive officers is outlined in the definitive proxy statement for the 2025 Annual Meeting of Stockholders, which was filed with the SEC on June 9, 2025, and information about their ownership of Plug’s stock is outlined in the definitive proxy statement for the Special Meeting filed with the SEC on December 12, 2025.

MEDIA CONTACT:

Teal Hoyos

Plug Power Inc.

Email: media@plugpower.com