<SEC-DOCUMENT>0001104659-17-005020.txt : 20170130
<SEC-HEADER>0001104659-17-005020.hdr.sgml : 20170130
<ACCEPTANCE-DATETIME>20170130174311
ACCESSION NUMBER:		0001104659-17-005020
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170126
FILED AS OF DATE:		20170130
DATE AS OF CHANGE:		20170130

ISSUER:		

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

	BUSINESS ADDRESS:	
		STREET 1:		968 ALBANY-SHAKER ROAD
		CITY:			LATHAM
		STATE:			NY
		ZIP:			12110
		BUSINESS PHONE:		5187827700

	MAIL ADDRESS:	
		STREET 1:		968 ALBANY-SHAKER ROAD
		CITY:			LATHAM
		STATE:			NY
		ZIP:			12110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Roth Johannes Minho
		CENTRAL INDEX KEY:			0001590334

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34392
		FILM NUMBER:		17558651

	MAIL ADDRESS:	
		STREET 1:		C/O PLUG POWER INC.
		STREET 2:		968 ALBANY SHAKER ROAD
		CITY:			LATHAM
		STATE:			NY
		ZIP:			12110
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-01-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001590334</rptOwnerCik>
            <rptOwnerName>Roth Johannes Minho</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PLUG POWER INC.</rptOwnerStreet1>
            <rptOwnerStreet2>968 ALBANY SHAKER ROAD</rptOwnerStreet2>
            <rptOwnerCity>LATHAM</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>12110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Series C Redeemable Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-01-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2620</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1256.81</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2782075</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2620</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Series C Redeemable Convertible Preferred Stock (the &quot;Series C Preferred Stock&quot;) is convertible at any time at the option of the holder into shares of the Issuer's Common Stock at a conversion price per share of $0.2343, subject to certain adjustments. The Series C Preferred Stock has no expiration date.</footnote>
        <footnote id="F2">On January 26, 2017, FiveT Capital Holding AG, a limited liability company existing under the laws of Switzerland (&quot;FiveT Capital Holding&quot;), and Five More Special Situations Fund Limited, a Cayman Islands company (&quot;FiveMore Fund&quot;), purchased 1,750 shares and 870 shares, respectively, of the Series C Preferred Stock for an aggregate purchase price of $3,292,850, or $1,256.81 per share.</footnote>
        <footnote id="F3">The reporting person is the Managing Director and Chairman of FiveT Capital Holding and has equity interests in each of FiveT Capital Holding and FiveMore Fund.  A wholly-owned subsidiary of FiveT Capital Holding provides investment advisory services to FiveMore Fund.  The reporting person disclaims beneficial ownership of the shares of Series C Preferred Stock directly held by FiveT Capital Holding and FiveMore Fund, except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed an admission that he is the beneficial owner of any ofsuch shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Gerard L. Conway Jr., Attorney-in-Fact</signatureName>
        <signatureDate>2017-01-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
