PLUG POWER INC

Item 5 (a) –

Termination of Material Definitive Agreement

As previously disclosed in the Current Report on Form 8-K filed by the Company with the SEC on January 23, 2025, on January 16, 2025, Plug Power Energy Loan Borrower LLC and Plug Power Limestone, LLC (the “Borrower Parties”) entered into the Loan Guarantee Agreement with the DOE. The Loan Guarantee Agreement provided for a loan guarantee of up to $1.66 billion through the DOE's Loan Programs Office (subsequently reorganized as DOE's Office of Energy Dominance Financing) to finance the development, construction, and ownership of up to six green hydrogen production facilities.

On August 4, 2026, the Company and the Borrower Parties received a notification letter (the “Termination Notice”) from the DOE exercising its right under Section 2.02(c) of the Loan Guarantee Agreement to terminate that agreement because the Initial First Advance had not occurred by the Initial First Advance Longstop Date (each as defined in the Loan Guarantee Agreement), consistent with the Company's previously disclosed decision, announced in November 2025, to suspend activities related to the projects that were to be financed under the Loan Guarantee Agreement. The Termination Notice provides that, automatically and without any further action by the DOE, upon the lapse of the ten business day notice period, (i) the Loan Guarantee Agreement will terminate, (ii) the Release Date (as defined in the Loan Guarantee Agreement) will occur and (iii) the DOE consents to the termination of the other financing documents entered into in connection with the Loan Guarantee Agreement. The Release Date is expected to occur on or around August 18, 2026.

No amounts were advanced or drawn under the Loan Guarantee Agreement. Accordingly, the Company does not expect the termination to result in any repayment, prepayment or termination-fee obligation. See Note 20, “Subsequent

Events,” to the unaudited interim condensed consolidated financial statements included in Part I, Item 1 of this Quarterly Report on Form 10-Q for additional information.

Upon the Release Date, the security interest granted by the Borrower Parties will terminate, and the Termination Notice directs the collateral agent to cooperate with the release of the related collateral, including the filing of UCC termination statements.

The foregoing description of the Termination Notice is not complete and is qualified in its entirety by reference to the full text of such notice, a copy of which is filed herewith as Exhibit 10.4 to this Quarterly Report on Form 10-Q and is incorporated herein by reference.

Item 5 (b) – Not applicable.

Item 5 (c) –

Director and Officer Trading Arrangements

On May 22, 2026, Gregory Kenausis, amember of the Company’s Board of Directors, modified his existing stock trading plan established pursuant to Rule 10b5-1 of the Exchange Act, which is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c), and which provides for the sale of up to 189,000 shares of the Company’s common stock commencingno earlier than August 21, 2026 through November 22, 2027. The plan was modified during an open insider trading window.

On May 28, 2026, Andrew Marsh, the Executive Chairman of the Company’s Board of Directors, adopted a new stock trading plan established pursuant to Rule 10b5-1 of the Exchange Act which is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c), and which provides for the sale of up to 600,001 shares of the Company’s common stock commencingno earlier than August 27, 2026 through November 22, 2027. The new plan was adopted during an open insider trading window.

On June 10, 2026, Colin Angle, amember of the Company’s Board of Directors, adopted a new stock trading plan established pursuant to Rule 10b5-1 of the Exchange Act which is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c), and which provides for (1) the sale of up to 28,691 shares of the Company’s common stock and (2) the sale of 40% of net shares of restricted stock awards of the Company’s common stock commencingno earlier than September 9, 2026 through June 10, 2027. The new plan was adopted during an open insider trading window.

On June 11, 2026, Benjamin Haycraft, the Company’s Chief Strategy Officer, adopted a new stock trading plan established pursuant to Rule 10b5-1 of the Exchange Act, which is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c), and which provides for the sale of up to 811,976 shares of the Company’s common stock in theaggregate between September 11, 2026 and December 31, 2027. The new plan was adopted during an open insider trading window.