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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 WyNLEBT6n9LDpb2MpgRNvCtXRN7ifWlwQK+LJaltMktNYMs8OyWpQycW8MOjQUZx
 6y/UnL2/TYFNB+AioLaI+Q==

<SEC-DOCUMENT>0001140361-10-051705.txt : 20101230
<SEC-HEADER>0001140361-10-051705.hdr.sgml : 20101230
<ACCEPTANCE-DATETIME>20101230170122
ACCESSION NUMBER:		0001140361-10-051705
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101229
FILED AS OF DATE:		20101230
DATE AS OF CHANGE:		20101230

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COWEN GROUP, INC.
		CENTRAL INDEX KEY:			0001466538
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				000000000
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1221 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10020
		BUSINESS PHONE:		(646) 562-1000

	MAIL ADDRESS:	
		STREET 1:		1221 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10020

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LexingtonPark Parent Corp
		DATE OF NAME CHANGE:	20090617

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RCG HOLDINGS LLC
		CENTRAL INDEX KEY:			0001050154
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34516
		FILM NUMBER:		101281745

	BUSINESS ADDRESS:	
		STREET 1:		599 LEXINGTON AVENUE
		STREET 2:		20TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		2122014823

	MAIL ADDRESS:	
		STREET 1:		599 LEXINGTON AVENUE
		STREET 2:		20TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	FORMER NAME:	
		FORMER CONFORMED NAME:	RAMIUS LLC
		DATE OF NAME CHANGE:	20080617

	FORMER NAME:	
		FORMER CONFORMED NAME:	RAMIUS CAPITAL GROUP LLC
		DATE OF NAME CHANGE:	20010212
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-12-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001466538</issuerCik>
        <issuerName>COWEN GROUP, INC.</issuerName>
        <issuerTradingSymbol>COWN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001050154</rptOwnerCik>
            <rptOwnerName>RCG HOLDINGS LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O COWEN GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>599 LEXINGTON AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-12-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3676072</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33576099</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares distributed to certain non-affiliate members of the Reporting Person who are withdrawing one-third of their capital from the Reporting Person as of December 31, 2010.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Owen S. Littman</signatureName>
        <signatureDate>2010-12-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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