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        <entityName>LOOMIS SAYLES SENIOR LOAN FUND LLC</entityName>
        <issuerAddress>
            <street1>ONE FINANCIAL CENTER</street1>
            <city>BOSTON</city>
            <stateOrCountry>MA</stateOrCountry>
            <zipCode>02111</zipCode>
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        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
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        <entityType>Limited Liability Company</entityType>
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                <middleName>JAMES</middleName>
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                <stateOrCountry>MA</stateOrCountry>
                <zipCode>02111</zipCode>
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                <lastName>RYAN</lastName>
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        <relatedPersonInfo>
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    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Hedge Fund</investmentFundType>
                <is40Act>false</is40Act>
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        </industryGroup>
        <issuerSize>
            <aggregateNetAssetValueRange>Decline to Disclose</aggregateNetAssetValueRange>
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        <federalExemptionsExclusions>
            <item>06</item>
            <item>3C</item>
            <item>3C.7</item>
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        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>9999999997-09-013920</previousAccessionNumber>
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            <dateOfFirstSale>
                <value>2004-07-01</value>
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        </typeOfFiling>
        <durationOfOffering>
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        <typesOfSecuritiesOffered>
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        <businessCombinationTransaction>
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            <clarificationOfResponse></clarificationOfResponse>
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        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>1464548328</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>109</totalNumberAlreadyInvested>
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        <salesCommissionsFindersFees>
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            <clarificationOfResponse></clarificationOfResponse>
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        <signatureBlock>
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            <signature>
                <issuerName>LOOMIS SAYLES SENIOR LOAN FUND LLC</issuerName>
                <signatureName>JEFFREY MEYER</signatureName>
                <nameOfSigner>JEFFREY MEYER</nameOfSigner>
                <signatureTitle>VICE PRESIDENT</signatureTitle>
                <signatureDate>2010-03-03</signatureDate>
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