<SEC-DOCUMENT>0001235468-21-000085.txt : 20210219
<SEC-HEADER>0001235468-21-000085.hdr.sgml : 20210219
<ACCEPTANCE-DATETIME>20210219172924
ACCESSION NUMBER:		0001235468-21-000085
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210217
FILED AS OF DATE:		20210219
DATE AS OF CHANGE:		20210219

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ELLIS GEORGE H
		CENTRAL INDEX KEY:			0001085715

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-51813
		FILM NUMBER:		21657351

	MAIL ADDRESS:	
		STREET 1:		2911 TURTLE CREEK BOULEVARD
		STREET 2:		SUITE 1100
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75219

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LIQUIDITY SERVICES INC
		CENTRAL INDEX KEY:			0001235468
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-BUSINESS SERVICES, NEC [7389]
		IRS NUMBER:				522209244
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		6931 ARLINGTON ROAD
		STREET 2:		SUITE 200
		CITY:			BETHESDA
		STATE:			MD
		ZIP:			20814
		BUSINESS PHONE:		2024676868

	MAIL ADDRESS:	
		STREET 1:		6931 ARLINGTON ROAD
		STREET 2:		SUITE 200
		CITY:			BETHESDA
		STATE:			MD
		ZIP:			20814
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161377371439630.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2021-02-17</periodOfReport>

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        <issuerName>LIQUIDITY SERVICES INC</issuerName>
        <issuerTradingSymbol>LQDT</issuerTradingSymbol>
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            <rptOwnerName>ELLIS GEORGE H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LIQUIDITY SERVICES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>6931 ARLINGTON ROAD, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>BETHESDA</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20814</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
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            <otherText></otherText>
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                <value>Common Stock</value>
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            <transactionDate>
                <value>2021-02-17</value>
            </transactionDate>
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                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>5181</value>
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                <transactionPricePerShare>
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                    <value>D</value>
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        <derivativeHolding>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
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                <value>6.29</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2017-02-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2026-02-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Grant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
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            <exerciseDate>
                <footnoteId id="F3"/>
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                <value>2022-02-01</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4655.0</value>
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                    <value>4655</value>
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        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">George H. Ellis Individual Retirement Account with Northern Trust Company as Trustee.</footnote>
        <footnote id="F2">Each restricted stock unit is the economic equivalent of one share of Liquidity Services, Inc. Common Stock.</footnote>
        <footnote id="F3">These restricted stock units vest on February 1, 2022.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mark A. Shaffer, by power of attorney</signatureName>
        <signatureDate>2021-02-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
