Plug Power

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-06-25 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: PLUG POWER INC (PLUG) CIK: 0001093691 --- Reporting Owner --- Name: MIDDLETON PAUL B CIK: 0001224978 Role: Officer (CFO & Executive VP) --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-06-25 | Code: A (Grant or award) Shares: +389,105 | Price: $0.00 Shares Owned After: 2,947,169 | Ownership: D (Direct) Footnotes: [F1] Consists of a restricted stock award made pursuant to the Plug Power Inc. 2021 Stock Option and Incentive Plan, as amended. The restricted shall vest in three equal annual installments following the grant date, subject to the Reporting Person's continued service on each such vesting date. --- Derivative Transactions --- [Transaction #1] Security: Stock Option (Right to Buy) Date: 2026-06-25 | Code: A (Grant or award) Shares: +510,204 | Price: $0.00 Exercisable: N/A | Expires: 2036-06-25 Shares Owned After: 510,204 | Ownership: D (Direct) Footnotes: [F3] Awarded pursuant to Plug Power Inc.'s 2021 Stock Option and Incentive Plan, as amended. [F4] The shares underlying this stock option shall vest in three equal annual installments following the grant date, subject to the Reporting Person's continued service on each such vesting date. --- Holdings --- [Holding #1] Security: Common Stock Ownership: I (Indirect) Footnotes: [F2] The Reporting Person holds 64,492 shares of common stock in Plug Power Inc.'s 401(k) plan. The information in this report is based on a plan statement as of June 29, 2026. --- Footnotes (Complete Index) --- F1: Consists of a restricted stock award made pursuant to the Plug Power Inc. 2021 Stock Option and Incentive Plan, as amended. The restricted shall vest in three equal annual installments following the grant date, subject to the Reporting Person's continued service on each such vesting date. F2: The Reporting Person holds 64,492 shares of common stock in Plug Power Inc.'s 401(k) plan. The information in this report is based on a plan statement as of June 29, 2026. F3: Awarded pursuant to Plug Power Inc.'s 2021 Stock Option and Incentive Plan, as amended. F4: The shares underlying this stock option shall vest in three equal annual installments following the grant date, subject to the Reporting Person's continued service on each such vesting date. --- Signature --- /s/ /s/ Gerard L. Conway, Jr., Attorney-in-Fact (2026-06-29)