<SEC-DOCUMENT>0001213900-11-006808.txt : 20111222
<SEC-HEADER>0001213900-11-006808.hdr.sgml : 20111222
<ACCEPTANCE-DATETIME>20111222154725
ACCESSION NUMBER:		0001213900-11-006808
CONFORMED SUBMISSION TYPE:	D
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Rule 506
FILED AS OF DATE:		20111222
DATE AS OF CHANGE:		20111222
EFFECTIVENESS DATE:		20111222

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EXAGEN DIAGNOSTICS INC
		CENTRAL INDEX KEY:			0001274737
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		D
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-170596
		FILM NUMBER:		111277435

	BUSINESS ADDRESS:	
		STREET 1:		801 UNIVERSITY SE
		STREET 2:		SUITE 209
		CITY:			ALBUQUERQUE
		STATE:			NM
		ZIP:			87106
		BUSINESS PHONE:		505-272-7966

	MAIL ADDRESS:	
		STREET 1:		801 UNIVERSITY BLVD. SE
		CITY:			ALBUQUERQUE
		STATE:			NM
		ZIP:			87106
</SEC-HEADER>
<DOCUMENT>
<TYPE>D
<SEQUENCE>1
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        <cik>0001274737</cik>
        <entityName>EXAGEN DIAGNOSTICS INC</entityName>
        <issuerAddress>
            <street1>801 UNIVERSITY BLVD. SE</street1>
            <street2>SUITE 103</street2>
            <city>ALBUQUERQUE</city>
            <stateOrCountry>NM</stateOrCountry>
            <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
            <zipCode>87106</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>505-272-7966</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
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        <entityType>Corporation</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
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    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Fortunato</firstName>
                <middleName>R.</middleName>
                <lastName>Rocca</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>801 UNIVERSITY BOULEVARD SE</street1>
                <street2>SUITE 103</street2>
                <city>ALBUQUERQUE</city>
                <stateOrCountry>NM</stateOrCountry>
                <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
                <zipCode>87106</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Thierry</firstName>
                <lastName>Dervieux</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>801 UNIVERSITY BOULEVARD SE</street1>
                <street2>SUITE 103</street2>
                <city>ALBUQUERQUE</city>
                <stateOrCountry>NM</stateOrCountry>
                <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
                <zipCode>87106</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>David</firstName>
                <lastName>Blivin</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>228 GRIFFIN STREET</street1>
                <city>SANTA FE</city>
                <stateOrCountry>NM</stateOrCountry>
                <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
                <zipCode>87501</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Wendy</firstName>
                <lastName>Swedick</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>801 UNIVERSITY BOULEVARD SE</street1>
                <street2>SUITE 103</street2>
                <city>ALBUQUERQUE</city>
                <stateOrCountry>NM</stateOrCountry>
                <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
                <zipCode>87106</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Brian</firstName>
                <lastName>Birk</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>301 GRIFFIN STREET</street1>
                <city>SANTA FE</city>
                <stateOrCountry>NM</stateOrCountry>
                <stateOrCountryDescription>NEW MEXICO</stateOrCountryDescription>
                <zipCode>87501</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Dinesh</firstName>
                <lastName>Patel</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2795 E. COTTONWOOD PARKWAY</street1>
                <street2>SUITE 360</street2>
                <city>SALT LAKE CITY</city>
                <stateOrCountry>UT</stateOrCountry>
                <stateOrCountryDescription>UTAH</stateOrCountryDescription>
                <zipCode>84121</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Sam</firstName>
                <lastName>Riccitelli</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1131 VIA FELICITA</street1>
                <city>ENCINITAS</city>
                <stateOrCountry>CA</stateOrCountry>
                <stateOrCountryDescription>CALIFORNIA</stateOrCountryDescription>
                <zipCode>92024</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Michael</firstName>
                <middleName>J.</middleName>
                <lastName>Walsh</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>P.O. BOX 3125</street1>
                <city>DEL MAR</city>
                <stateOrCountry>CA</stateOrCountry>
                <stateOrCountryDescription>CALIFORNIA</stateOrCountryDescription>
                <zipCode>92014</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Curtis</firstName>
                <lastName>LaBelle</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>ONE STAMFORD PLAZA</street1>
                <street2>263 TRESSER BOULEVARD</street2>
                <city>STAMFORD</city>
                <stateOrCountry>CT</stateOrCountry>
                <stateOrCountryDescription>CONNECTICUT</stateOrCountryDescription>
                <zipCode>06901</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Biotechnology</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>$1,000,001 - $5,000,000</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2011-12-19</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>24709488</totalOfferingAmount>
            <totalAmountSold>11986707</totalAmountSold>
            <totalRemaining>12722781</totalRemaining>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>9</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>1600000</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>EXAGEN DIAGNOSTICS INC</issuerName>
                <signatureName>/s/ Wendy Swedick</signatureName>
                <nameOfSigner>Wendy Swedick</nameOfSigner>
                <signatureTitle>Chief Financial Officer</signatureTitle>
                <signatureDate>2011-12-22</signatureDate>
            </signature>
        </signatureBlock>
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</SEC-DOCUMENT>
