<SEC-DOCUMENT>0001179110-17-014753.txt : 20171201
<SEC-HEADER>0001179110-17-014753.hdr.sgml : 20171201
<ACCEPTANCE-DATETIME>20171201082703
ACCESSION NUMBER:		0001179110-17-014753
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171201
FILED AS OF DATE:		20171201
DATE AS OF CHANGE:		20171201

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			McMahon Gerald PhD
		CENTRAL INDEX KEY:			0001290747

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15006
		FILM NUMBER:		171232750

	MAIL ADDRESS:	
		STREET 1:		300 ELLIOTT AVENUE WEST
		STREET 2:		SUITE 500
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98119-4114

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Celldex Therapeutics, Inc.
		CENTRAL INDEX KEY:			0000744218
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		IRS NUMBER:				133191702
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		53 FRONTAGE ROAD
		STREET 2:		SUITE 220
		CITY:			HAMPTON
		STATE:			NJ
		ZIP:			08827
		BUSINESS PHONE:		908-200-7500

	MAIL ADDRESS:	
		STREET 1:		53 FRONTAGE ROAD
		STREET 2:		SUITE 220
		CITY:			HAMPTON
		STATE:			NJ
		ZIP:			08827

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AVANT IMMUNOTHERAPEUTICS INC
		DATE OF NAME CHANGE:	19980828

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	T CELL SCIENCES INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-12-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000744218</issuerCik>
        <issuerName>Celldex Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>CLDX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001290747</rptOwnerCik>
            <rptOwnerName>McMahon Gerald PhD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CELLDEX THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>53  FRONTAGE ROAD, SUITE 220</rptOwnerStreet2>
            <rptOwnerCity>HAMPTON</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08827</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2017-12-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3212</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>217236</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On November 28, 2016, in connection with the Reporting Person's employment separation agreement with Kolltan Pharmaceuticals, Inc., Reporting Person entered into a severance agreement (the &quot;Severance Agreement&quot;) with Celldex Therapeutics, Inc. (&quot;Issuer&quot;) whereby Issuer agreed to pay Reporting Person 267,356 shares of its common stock, par value $0.001 per share (&quot;Common Stock&quot;) less required tax and other withholdings (the &quot;Withholdings&quot;.)  The Reporting Person previously reported ownership of such 267,356 shares on his Form 3 filed with the Securities and Exchange Commission on December 15, 2016.  The shares, less Withholdings, are issuable to Reporting Person in equal monthly installments through December 2018.</footnote>
        <footnote id="F2">Pursuant to the Severance Agreement, on December 1, 2017, the Issuer issued 5,142 shares of its Common Stock to the Reporting Person.  This Form 4 reflects the disposition to the Issuer of 3,212 shares of its Common Stock to satisfy required Withholdings in connection with such issuance of Common Stock to the Reporting Person.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Samuel B. Martin, attorney-in-fact for Gerald McMahon</signatureName>
        <signatureDate>2017-12-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
