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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001077870-10-000004.txt : 20100311
<SEC-HEADER>0001077870-10-000004.hdr.sgml : 20100311
<ACCEPTANCE-DATETIME>20100311150217
ACCESSION NUMBER:		0001077870-10-000004
CONFORMED SUBMISSION TYPE:	D/A
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Rule 506
ITEM INFORMATION:		Investment Company Act Section 3(c)
ITEM INFORMATION:		Section 3(c)(1)
FILED AS OF DATE:		20100311
DATE AS OF CHANGE:		20100311
EFFECTIVENESS DATE:		20100311

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNION SPRING FUND (USA) L.P.
		CENTRAL INDEX KEY:			0001077870
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		D/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-129477
		FILM NUMBER:		10673755

	BUSINESS ADDRESS:	
		STREET 1:		101 MORGAN LANE
		STREET 2:		SUITE 180
		CITY:			PLAINSBORO
		STATE:			NJ
		ZIP:			08536
		BUSINESS PHONE:		609-936-1100

	MAIL ADDRESS:	
		STREET 1:		101 MORGAN LANE, SUITE 180
		CITY:			PLAINSBORO
		STATE:			NJ
		ZIP:			08536

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	UNION SPRING FUND USA LP
		DATE OF NAME CHANGE:	19990129
</SEC-HEADER>
<DOCUMENT>
<TYPE>D/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
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    <schemaVersion>X0603</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001077870</cik>
        <entityName>UNION SPRING FUND (USA) L.P.</entityName>
        <issuerAddress>
            <street1>101 MORGAN LANE</street1>
            <street2>SUITE 180</street2>
            <city>PLAINSBORO</city>
            <stateOrCountry>NJ</stateOrCountry>
            <zipCode>08536</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>609-936-1100</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <edgarPreviousNameList>
            <previousName>UNION SPRING FUND USA LP</previousName>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>PHILIP</firstName>
                <middleName>L.</middleName>
                <lastName>YANG, JR.</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>STEVEN</firstName>
                <middleName>R.</middleName>
                <lastName>CRANE</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>MICHAEL</firstName>
                <middleName>Y.</middleName>
                <lastName>GAN</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>RICHARD</firstName>
                <middleName>G.</middleName>
                <lastName>FAUX, JR.</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>EDWARD</firstName>
                <middleName>T.</middleName>
                <lastName>DUNNE</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>JAMES</firstName>
                <middleName>J.</middleName>
                <lastName>O'DONNELL</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>VIRGINIA</firstName>
                <middleName>M.</middleName>
                <lastName>LOEBEL</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>JANICE</firstName>
                <middleName>A.</middleName>
                <lastName>KIOKO</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>C/O WILLOWBRIDGE ASSOCIATES INC.</street1>
                <street2>101 MORGAN LANE, SUITE 180</street2>
                <city>PLAINSBORO</city>
                <stateOrCountry>NJ</stateOrCountry>
                <zipCode>08536</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Hedge Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <aggregateNetAssetValueRange>Decline to Disclose</aggregateNetAssetValueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
            <item>3C</item>
            <item>3C.1</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>9999999997-09-014867</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>1998-04-01</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>true</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>1000000</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>112801263</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>41</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>UNION SPRING FUND (USA) L.P.</issuerName>
                <signatureName>STEVEN R. CRANE</signatureName>
                <nameOfSigner>STEVEN R. CRANE</nameOfSigner>
                <signatureTitle>SECRETARY OF THE GENERAL PARTNER OF THE ISSUER</signatureTitle>
                <signatureDate>2010-03-11</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----