<SEC-DOCUMENT>0001104659-25-070387.txt : 20250724
<SEC-HEADER>0001104659-25-070387.hdr.sgml : 20250724
<ACCEPTANCE-DATETIME>20250724162118
ACCESSION NUMBER:		0001104659-25-070387
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250703
FILED AS OF DATE:		20250724
DATE AS OF CHANGE:		20250724

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mahtani Kavita
		CENTRAL INDEX KEY:			0001923759
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34392
		FILM NUMBER:		251147161

	MAIL ADDRESS:	
		STREET 1:		C/O PLUG POWER INC.
		STREET 2:		968 ALBANY SHAKER ROAD
		CITY:			LATHAM
		STATE:			NY
		ZIP:			12110

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PLUG POWER INC
		CENTRAL INDEX KEY:			0001093691
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRICAL INDUSTRIAL APPARATUS [3620]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				223672377
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		125 VISTA BOULEVARD
		CITY:			SLINGERLANDS
		STATE:			NY
		ZIP:			12159
		BUSINESS PHONE:		5187827700

	MAIL ADDRESS:	
		STREET 1:		125 VISTA BOULEVARD
		CITY:			SLINGERLANDS
		STATE:			NY
		ZIP:			12159
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>tm2521653-7_4seq1.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
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<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-07-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001093691</issuerCik>
        <issuerName>PLUG POWER INC</issuerName>
        <issuerTradingSymbol>PLUG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001923759</rptOwnerCik>
            <rptOwnerName>Mahtani Kavita</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PLUG POWER INC.</rptOwnerStreet1>
            <rptOwnerStreet2>125 VISTA BOULEVARD</rptOwnerStreet2>
            <rptOwnerCity>SLINGERLANDS</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>12159</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-07-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>76531</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>208813</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.47</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-07-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>76531</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2035-07-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>76531</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>76531</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Consists of a restricted stock award made pursuant to the Plug Power Inc. 2021 Stock Option and Incentive Plan, as amended, in accordance with the Non-Employee Director Compensation Plan. The restricted stock shall vest in full on the earlier of (i) first anniversary of the grant date or (ii) the date of the next annual meeting which is at least fifty (50) weeks after the immediately preceding year's annual meeting.</footnote>
        <footnote id="F2">Stock option granted pursuant to the Plug Power Inc. 2021 Stock Option and Incentive Plan, as amended, in accordance with the Non-Employee Director Compensation Plan.</footnote>
        <footnote id="F3">The options shall vest in full on the earlier of (i) first anniversary of the grant date or (ii) the date of the next annual meeting which is at least fifty (50) weeks after the immediately preceding year's annual meeting.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Gerard L. Conway Jr., Attorney-in-Fact</signatureName>
        <signatureDate>2025-07-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
