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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 BBXmAik97sDCA3a/tjAJf+FqyBk64w2Yr7+461ICKJN19q+TQ6IqNaDnULXS4q6h
 5F001B4WAwC/Cu8KTg/B0g==

<SEC-DOCUMENT>0001213798-09-000015.txt : 20090402
<SEC-HEADER>0001213798-09-000015.hdr.sgml : 20090402
<ACCEPTANCE-DATETIME>20090402162159
ACCESSION NUMBER:		0001213798-09-000015
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090331
FILED AS OF DATE:		20090402
DATE AS OF CHANGE:		20090402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mergenthaler Frank
		CENTRAL INDEX KEY:			0001334911

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06686
		FILM NUMBER:		09727930

	MAIL ADDRESS:	
		STREET 1:		1114 AVENUE OF THE AMERICAS
		STREET 2:		19TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INTERPUBLIC GROUP OF COMPANIES, INC.
		CENTRAL INDEX KEY:			0000051644
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ADVERTISING AGENCIES [7311]
		IRS NUMBER:				131024020
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1114 AVENUE OF THE AMERICAS
		STREET 2:		19TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036
		BUSINESS PHONE:		212-704-1200

	MAIL ADDRESS:	
		STREET 1:		1114 AVENUE OF THE AMERICAS
		STREET 2:		16TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERPUBLIC GROUP OF COMPANIES INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MCCANN ERICKSON INC
		DATE OF NAME CHANGE:	19710715
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-03-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000051644</issuerCik>
        <issuerName>INTERPUBLIC GROUP OF COMPANIES, INC.</issuerName>
        <issuerTradingSymbol>IPG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001334911</rptOwnerCik>
            <rptOwnerName>Mergenthaler Frank</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1114 AVENUE OF THE AMERICAS</rptOwnerStreet1>
            <rptOwnerStreet2>19TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-03-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>80515</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.14</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>468274</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock that will vest as of March 31, 2012.</footnote>
        <footnote id="F2">Includes restricted shares that are subject to forfeiture under certain circumstances.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Nicholas J. Camera POA for Frank Mergenthaler</signatureName>
        <signatureDate>2009-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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