-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 UkWmAyzLiKU+GEGVIJOaXlkwVXQ8QYZxN0heXuVLpUcPCzO/JMOprtJEAS1tPLpp
 mh10am/jaI8lalFI2xJVUQ==

<SEC-DOCUMENT>0001179110-09-003469.txt : 20090225
<SEC-HEADER>0001179110-09-003469.hdr.sgml : 20090225
<ACCEPTANCE-DATETIME>20090225182525
ACCESSION NUMBER:		0001179110-09-003469
CONFORMED SUBMISSION TYPE:	3/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090210
FILED AS OF DATE:		20090225
DATE AS OF CHANGE:		20090225

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Thadaney Nicholas
		CENTRAL INDEX KEY:			0001456721

	FILING VALUES:
		FORM TYPE:		3/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32722
		FILM NUMBER:		09635095

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		212-588-4000

	MAIL ADDRESS:	
		STREET 1:		C/O ITG INC.
		STREET 2:		380 MADISON AVENUE
		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:		4TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		2125884000

	MAIL ADDRESS:	
		STREET 1:		380 MADISON AVE
		STREET 2:		4TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
</SEC-HEADER>
<DOCUMENT>
<TYPE>3/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 3/A -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0203</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2009-02-10</periodOfReport>

    <dateOfOriginalSubmission>2009-02-20</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000920424</issuerCik>
        <issuerName>INVESTMENT TECHNOLOGY GROUP INC</issuerName>
        <issuerTradingSymbol>ITG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001456721</rptOwnerCik>
            <rptOwnerName>Thadaney Nicholas</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>Man. Director, CEO of Canada</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11469</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>45.3</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2009-08-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2011-08-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5400</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>47.59</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2011-01-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-01-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12901</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Unit (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30860</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">With respect to the entire class of Stock Units: 8,572 vest on 2/6/2010, 8,572 vest on 2/6/2011, and 13,716 vest on 2/6/2012.</footnote>
        <footnote id="F2">Cash settlement of Stock Units occurs on the vesting dates as set forth in Footnote 1.</footnote>
        <footnote id="F3">One-for-one</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>P. Mats Goebels, by Power of Attorney filed with Form 3 dated February 20, 2009</signatureName>
        <signatureDate>2009-02-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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