<SEC-DOCUMENT>0001104659-20-102242.txt : 20200903
<SEC-HEADER>0001104659-20-102242.hdr.sgml : 20200903
<ACCEPTANCE-DATETIME>20200903161628
ACCESSION NUMBER:		0001104659-20-102242
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200901
FILED AS OF DATE:		20200903
DATE AS OF CHANGE:		20200903

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lavieri Todd D.
		CENTRAL INDEX KEY:			0001760914

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33287
		FILM NUMBER:		201159435

	MAIL ADDRESS:	
		STREET 1:		C/O INFORMATION SERVICES GROUP, INC.
		STREET 2:		2187 ATLANTIC STREET
		CITY:			STAMFORD
		STATE:			CT
		ZIP:			06902

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Information Services Group Inc.
		CENTRAL INDEX KEY:			0001371489
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MANAGEMENT CONSULTING SERVICES [8742]
		IRS NUMBER:				205261587
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2187 ATLANTIC STREET
		CITY:			STAMFORD
		STATE:			CT
		ZIP:			06902
		BUSINESS PHONE:		203-517-3100

	MAIL ADDRESS:	
		STREET 1:		2187 ATLANTIC STREET
		CITY:			STAMFORD
		STATE:			CT
		ZIP:			06902
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-09-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001371489</issuerCik>
        <issuerName>Information Services Group Inc.</issuerName>
        <issuerTradingSymbol>III</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001760914</rptOwnerCik>
            <rptOwnerName>Lavieri Todd D.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2187 ATLANTIC ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>STAMFORD</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06902</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice Chairman</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Shares of Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-09-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>173780</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>940113</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance-based RSUs</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-09-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>57927</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-09-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>57927</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>57927</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock units (RSUs)granted to the reporting person pursuant to the Information Services Group, Inc. Amended and Restated 2007 Equity and Incentive Award Plan, which will vest in 4 equal installments on each of the first, second, third and fourth anniversaries of September 1, 2020.</footnote>
        <footnote id="F2">Represents a grant of RSUs that may be earned based on achievement of market price goals, which will be measured at the average closing price of the Issuer's common stock over any consecutive ten-trading-day period prior to and including the fourth anniversary of the date of grant.  100% of the number of RSUs reported above will be earned if such measured market price is $5.25 or above. Unearned RSUs will be canceled.  Market price goals are subject to adjustment for stock splits and certain other corporate events.  Once determined, any such earned RSUs will be fully vested.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>David E. Berger, as attorney-in-fact</signatureName>
        <signatureDate>2020-09-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
