Plug Power

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-03-02 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: PLUG POWER INC (PLUG) CIK: 0001093691 --- Reporting Owner --- Name: Marsh Andrew CIK: 0001431827 Role: Director --- Derivative Transactions --- [Transaction #1] Security: Stock Option (Right to Buy) Date: 2026-03-02 | Code: A (Grant or award) Shares: +163,638 | Price: $0.00 Exercisable: N/A | Expires: 2036-03-02 Shares Owned After: 163,638 | Ownership: D (Direct) Footnotes: [F1] Awarded pursuant to Plug Power Inc.'s 2021 Stock Option and Incentive Plan, as amended. [F2] Stock option issued pursuant to the previously disclosed Non-Executive Chairman Agreement, pursuant to which the Reporting Person received an initial, one-time equity award. The shares underlying this stock option shall vest in full on March 2, 2027, subject to the Reporting Person's continued service on such vesting date. [Transaction #2] Security: Stock Option (Right to Buy) Date: 2026-03-31 | Code: A (Grant or award) Shares: +87,260 | Price: $0.00 Exercisable: N/A | Expires: 2036-03-31 Shares Owned After: 87,260 | Ownership: D (Direct) Footnotes: [F1] Awarded pursuant to Plug Power Inc.'s 2021 Stock Option and Incentive Plan, as amended. [F3] Stock option issued pursuant to the previously disclosed Transitional Consulting Agreement, pursuant to which the Reporting Person is entitled to receive a quarterly equity award during the term of the agreement. The shares underlying this stock option shall vest in three equal annual installments commencing on the first anniversary of the grant date, subject to the Reporting Person's continued service through each applicable vesting date. --- Footnotes (Complete Index) --- F1: Awarded pursuant to Plug Power Inc.'s 2021 Stock Option and Incentive Plan, as amended. F2: Stock option issued pursuant to the previously disclosed Non-Executive Chairman Agreement, pursuant to which the Reporting Person received an initial, one-time equity award. The shares underlying this stock option shall vest in full on March 2, 2027, subject to the Reporting Person's continued service on such vesting date. F3: Stock option issued pursuant to the previously disclosed Transitional Consulting Agreement, pursuant to which the Reporting Person is entitled to receive a quarterly equity award during the term of the agreement. The shares underlying this stock option shall vest in three equal annual installments commencing on the first anniversary of the grant date, subject to the Reporting Person's continued service through each applicable vesting date. --- Signature --- /s/ /s/ Gerard L. Conway, Jr., Attorney-in-Fact (2026-06-16)