<SEC-DOCUMENT>0001388670-17-000010.txt : 20170213
<SEC-HEADER>0001388670-17-000010.hdr.sgml : 20170213
<ACCEPTANCE-DATETIME>20170213180934
ACCESSION NUMBER:		0001388670-17-000010
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170209
FILED AS OF DATE:		20170213
DATE AS OF CHANGE:		20170213

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ON ASSIGNMENT INC
		CENTRAL INDEX KEY:			0000890564
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-HELP SUPPLY SERVICES [7363]
		IRS NUMBER:				954023433
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		26745 MALIBU HILLS ROAD
		CITY:			CALABASAS
		STATE:			CA
		ZIP:			91301
		BUSINESS PHONE:		8188787900

	MAIL ADDRESS:	
		STREET 1:		26745 MALIBU HILLS ROAD
		CITY:			CALABASAS
		STATE:			CA
		ZIP:			91301

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			McGowan Michael
		CENTRAL INDEX KEY:			0001388670

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35636
		FILM NUMBER:		17601269

	MAIL ADDRESS:	
		STREET 1:		100 CUMMINGS CENTER, SUITE 206L
		CITY:			BEVERLY
		STATE:			MA
		ZIP:			01915
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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        <issuerName>ON ASSIGNMENT INC</issuerName>
        <issuerTradingSymbol>ASGN</issuerTradingSymbol>
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            <rptOwnerName>McGowan Michael</rptOwnerName>
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            <rptOwnerStreet2>26745 MALIBU HILLS ROAD</rptOwnerStreet2>
            <rptOwnerCity>CALABASAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>91301</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Advisor, Board of Directors</otherText>
        </reportingOwnerRelationship>
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                <transactionCode>A</transactionCode>
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                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Trust</value>
                </natureOfOwnership>
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        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The acquired shares vested upon certification of performance targets on February 9, 2017, for performance awards previously granted to the executive officer.</footnote>
        <footnote id="F2">Executive officer elected to satisfy tax withholding obligations upon vesting of restricted stock units by having the issuer withhold a number of vested shares equal to that of the executive officer's tax liability.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Jennifer Painter, CLO For:  Michael J. McGowan</signatureName>
        <signatureDate>2017-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
