Material Event - Form 8-K

On May 24, 2024, Plug Power Inc. (the "Company") filed with the Securities and Exchange Commission a prospectus supplement (the "Prospectus Supplement") to its automatic shelf registration statement on Form S-3 (File No. 333-265488) relating to the resale by certain selling stockholders of up to 3,461,371 shares of the Company's common stock issuable upon exercise of the warrants that were issued to the selling stockholders pursuant to that certain Agreement and Plan of Merger, dated June 22, 2020 (as amended, supplemented or modified from time to time), by and among the Company, Giner ELX Sub, LLC, Giner ELX Merger Sub, Inc., Giner ELX, Inc., and Giner, Inc., as the representative of the stockholders.

In connection with the filing of the Prospectus Supplement, the Company is filing an opinion of its counsel, Goodwin Procter LLP, regarding the legality of the common stock issuable upon exercise of the warrants, which opinion is attached as Exhibit 5.1 to this Current Report on Form 8-K and incorporated herein by reference.