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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001181431-08-039293.txt : 20080617
<SEC-HEADER>0001181431-08-039293.hdr.sgml : 20080617
<ACCEPTANCE-DATETIME>20080617171132
ACCESSION NUMBER:		0001181431-08-039293
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080115
FILED AS OF DATE:		20080617
DATE AS OF CHANGE:		20080617

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FACTSET RESEARCH SYSTEMS INC
		CENTRAL INDEX KEY:			0001013237
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROGRAMMING, DATA PROCESSING, ETC. [7370]
		IRS NUMBER:				133362547
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0831

	BUSINESS ADDRESS:	
		STREET 1:		601 MERRITT 7
		CITY:			NORWALK
		STATE:			CT
		ZIP:			06851
		BUSINESS PHONE:		2038101000

	MAIL ADDRESS:	
		STREET 1:		601 MERRITT 7
		CITY:			NORWALK
		STATE:			CT
		ZIP:			06851

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SIEBECKER WALTER F
		CENTRAL INDEX KEY:			0001164872

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11869
		FILM NUMBER:		08903931

	BUSINESS ADDRESS:	
		STREET 1:		FACTSET RESEARCH SYSTEMS INC
		STREET 2:		ONE GREENWICH PLAZA
		CITY:			GREENWICH
		STATE:			CT
		ZIP:			06830
		BUSINESS PHONE:		2038631500

	MAIL ADDRESS:	
		STREET 1:		FACTSET RESEARCH SYHSTEMS INC
		STREET 2:		ONE GREENWICH PLAZA
		CITY:			GREENWICH
		STATE:			CT
		ZIP:			06830
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>rrd211036.xml
<DESCRIPTION>W. SIEBECKER AMENDED FORM 4 FROM 1.17.08
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2008-01-15</periodOfReport>

    <dateOfOriginalSubmission>2008-01-17</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001013237</issuerCik>
        <issuerName>FACTSET RESEARCH SYSTEMS INC</issuerName>
        <issuerTradingSymbol>FDS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001164872</rptOwnerCik>
            <rptOwnerName>SIEBECKER WALTER F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>601 MERRITT 7</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORWALK</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>FactSet Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-01-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>0</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-01-15</value>
            </exerciseDate>
            <expirationDate>
                <value>2008-01-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>FactSet Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <remarks>This Form 4 amends the previously filed Form 4 on January 17, 2008. No stock options were granted to FactSet's non-employee Directors, as originally expected, due to the inadvertent lapse and expiration of FactSet's 1998 Non-Employee Directors' Stock Option Plan on November 1, 2007. As such, the previously disclosed Director stock option grant on January 15, 2008 did not occur and is hereby corrected in this Form 4/A.</remarks>

    <ownerSignature>
        <signatureName>Walter F. Siebecker</signatureName>
        <signatureDate>2008-06-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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