    <SEC-DOCUMENT>0001193125-19-250698-index.html : 20190920
    <SEC-HEADER>0001193125-19-250698.hdr.sgml : 20190920
    <ACCEPTANCE-DATETIME>20190920161324
    ACCESSION NUMBER:		0001193125-19-250698
    CONFORMED SUBMISSION TYPE:	424B4
    PUBLIC DOCUMENT COUNT:		5
    FILED AS OF DATE:		20190920
    DATE AS OF CHANGE:		20190920

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			EXAGEN INC.
    		CENTRAL INDEX KEY:			0001274737
    		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEDICAL LABORATORIES [8071]
    		IRS NUMBER:				000000000
    		STATE OF INCORPORATION:			DE

    	FILING VALUES:
    		FORM TYPE:		424B4
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-233446
    		FILM NUMBER:		191104821

    	BUSINESS ADDRESS:
    		STREET 1:		1261 LIBERTY WAY
    		CITY:			VISTA
    		STATE:			CA
    		ZIP:			92081
    		BUSINESS PHONE:		(760) 560-1501

    	MAIL ADDRESS:
    		STREET 1:		1261 LIBERTY WAY
    		CITY:			VISTA
    		STATE:			CA
    		ZIP:			92081

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	EXAGEN DIAGNOSTICS INC
    		DATE OF NAME CHANGE:	20031230
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>424B4
    <SEQUENCE>1
    <FILENAME>d692844d424b4.htm
    <DESCRIPTION>424B4
    <TEXT>
    Document 1 - file: d692844d424b4.htm

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    <DESCRIPTION>GRAPHIC
    <TEXT>
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    <DOCUMENT>
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    <SEQUENCE>3
    <FILENAME>g692844g50a84.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: g692844g50a84.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
    <FILENAME>g692844g70h03.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: g692844g70h03.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>5
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    <DESCRIPTION>GRAPHIC
    <TEXT>
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