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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,
 DfR/gtc10OokQkCn/ivRyiV9/r3Qb7jgqHBhAGxal+ls/F40mZPqvxPKKBq+h6PI
 LDQQV7E5nxY+XVnsEFZccA==

<SEC-DOCUMENT>0001179110-03-009041.txt : 20031021
<SEC-HEADER>0001179110-03-009041.hdr.sgml : 20031021
<ACCEPTANCE-DATETIME>20031021165318
ACCESSION NUMBER:		0001179110-03-009041
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031015
FILED AS OF DATE:		20031021

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DOMOWITZ IAN
		CENTRAL INDEX KEY:			0001260365

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-78309
		FILM NUMBER:		03950188

	MAIL ADDRESS:	
		STREET 1:		C/O ITG INC
		STREET 2:		380 MADISON AVE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INVESTMENT TECHNOLOGY GROUP INC
		CENTRAL INDEX KEY:			0000920424
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				133757717
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		380 MADISON AVE
		STREET 2:		2ND FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		2125884000

	MAIL ADDRESS:	
		STREET 1:		11100 SANTA MONICA BLVD
		STREET 2:		12TH FLOOR
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90025
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-10-15</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000920424</issuerCik>
        <issuerName>INVESTMENT TECHNOLOGY GROUP INC</issuerName>
        <issuerTradingSymbol>ITG</issuerTradingSymbol>
</issuer>
<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001260365</rptOwnerCik>
            <rptOwnerName>DOMOWITZ IAN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ITG INC.</rptOwnerStreet1>
            <rptOwnerStreet2>380 MADISON AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Managing Director</officerTitle>
<otherText></otherText>
</reportingOwnerRelationship>
</reportingOwner>
<nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-10-15</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>1139</value>
</transactionShares>
<transactionPricePerShare><value>0</value>
<footnoteId id="F1"></footnoteId>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>9228</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
</nonDerivativeTable>
<derivativeTable></derivativeTable>
<footnotes><footnote id="F1">Grant of Stock Unit Award</footnote>
</footnotes>
<ownerSignature><signatureName>Sophia Lee, by Power of Attorney filed with Form 3 dated August 18, 2003</signatureName>
<signatureDate>2003-10-21</signatureDate>
</ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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