<SEC-DOCUMENT>0001628280-18-003958.txt : 20180403
<SEC-HEADER>0001628280-18-003958.hdr.sgml : 20180403
<ACCEPTANCE-DATETIME>20180403165022
ACCESSION NUMBER:		0001628280-18-003958
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180402
FILED AS OF DATE:		20180403
DATE AS OF CHANGE:		20180403

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Angrick William P III
		CENTRAL INDEX KEY:			0001352618

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-51813
		FILM NUMBER:		18734134

	MAIL ADDRESS:	
		STREET 1:		C/O LIQUIDITY SERVICES, INC.
		STREET 2:		1920 L STREET, N.W., 6TH FLOOR
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20036

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LIQUIDITY SERVICES INC
		CENTRAL INDEX KEY:			0001235468
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-BUSINESS SERVICES, NEC [7389]
		IRS NUMBER:				522209244
		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_152278858788578.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-04-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001235468</issuerCik>
        <issuerName>LIQUIDITY SERVICES INC</issuerName>
        <issuerTradingSymbol>LQDT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001352618</rptOwnerCik>
            <rptOwnerName>Angrick William P III</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>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman of the Board and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-04-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>24980</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.23</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
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                <sharesOwnedFollowingTransaction>
                    <value>3670563</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the William P. Angrick III Revocable Trust</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-04-02</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
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                </transactionShares>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3660090</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the William P. Angrick III Revocable Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>873379</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the William P. Angrick III 2005 Irrevocable Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>575513</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By the Stephanie S. Angrick 2005 Irrevocable Trust</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
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                    <value>114699</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
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                    <value>By the Stephanie S. Angrick Revocable Trust</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.92</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>130620.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>130620</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.92</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F6"/>
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            <expirationDate>
                <value>2027-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>87080.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>87080</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Grant</value>
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                <value>4.92</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F7"/>
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            <expirationDate>
                <value>2027-10-01</value>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
                    <value>12300.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12300</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
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                <sharesOwnedFollowingTransaction>
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                <value>Employee Stock Grant</value>
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            <securityTitle>
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            <underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
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                    <value>83178.0</value>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
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                <value>2024-10-01</value>
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                <underlyingSecurityShares>
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                    <value>29980</value>
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            <expirationDate>
                <value>2023-10-01</value>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
                    <value>48122.0</value>
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                <sharesOwnedFollowingTransaction>
                    <value>48122</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
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            <conversionOrExercisePrice>
                <value>46.72</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F16"/>
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            <expirationDate>
                <value>2022-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>14695.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14695</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
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        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
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            <conversionOrExercisePrice>
                <value>37.72</value>
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            <exerciseDate>
                <footnoteId id="F17"/>
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            <expirationDate>
                <value>2021-10-01</value>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
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                    <value>32139.0</value>
                </underlyingSecurityShares>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32139</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>17.02</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F18"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8641.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8641</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Grant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>15.47</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>11053.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11053</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>9.96</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F19"/>
            </exerciseDate>
            <expirationDate>
                <value>2019-10-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4568.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4568</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the vesting of restricted stock.</footnote>
        <footnote id="F2">These shares are held in a trust for the benefit of the reporting person. The reporting person disclaims beneficial ownership of these securities, and the filing of this report is not an admission that the reporting person is the beneficial owner of the securities for the purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F3">Represents an advance election by the insider to satisfy tax withholding obligations related to vesting of restricted shares by authorizing the issuer to sell a number of shares with an aggregate fair market value that would satisfy the withholding amount due.</footnote>
        <footnote id="F4">These shares are held in a trust for the benefit of the reporting person's spouse, who is also trustee of the trust. The reporting person disclaims beneficial ownership of these securities, and the filing of this report is not an admission that the reporting person is the beneficial owner of the securities for the purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F5">This option becomes exercisable, if at all, based on the Issuer's achievement of certain financial milestones.</footnote>
        <footnote id="F6">15/48th of this option grant will vest on January 1, 2019 and thereafter 1/48th of the option grant will vest each month for thirty three months.</footnote>
        <footnote id="F7">These restricted shares will vest, if at all, based on the Issuer's achievement of certain financial milestones.</footnote>
        <footnote id="F8">Twenty-five percent of this restricted stock grant will vest on January 1, 2019 and thereafter 1/4th of the restricted stock grant will vest on each October 1, 2019, October 1, 2020, and October 1, 2021.</footnote>
        <footnote id="F9">Twenty-five percent of this restricted stock grant vested on April 1, 2018 and thereafter 1/4th of the restricted stock grant will vest on each of October 1, 2018, October 1, 2019, and October 1, 2020.</footnote>
        <footnote id="F10">18/48th of this option grant vested on April 1, 2018 and thereafter 1/48th of the option grant will vest each month for thirty months.</footnote>
        <footnote id="F11">Twenty-five percent of this restricted stock grant vested on October 1, 2016 and thereafter 1/4th of the restricted stock grant will vest on October 1 of each year for three years.</footnote>
        <footnote id="F12">Twenty-five percent of this option grant vested on October 1, 2016 and thereafter 1/48th of the option grant will vest each month for thirty-six months.</footnote>
        <footnote id="F13">Twenty-five percent of this restricted stock grant vested on October 1, 2015 and thereafter 1/8th of the restricted stock grant will vest on April 1 and October 1 of each year for three years.</footnote>
        <footnote id="F14">Twenty-five percent of this option grant vested on October 1, 2015 and thereafter 1/48th of the option grant will vest each month for thirty-six months.</footnote>
        <footnote id="F15">These options became fully vested on October 1, 2017.</footnote>
        <footnote id="F16">These options became fully vested on October 1, 2016.</footnote>
        <footnote id="F17">These options became fully vested on October 1, 2015.</footnote>
        <footnote id="F18">These options became fully vested on October 1, 2014.</footnote>
        <footnote id="F19">These options became fully vested on October 1, 2013.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mark A. Shaffer, by power of attorney</signatureName>
        <signatureDate>2018-04-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
