<SEC-DOCUMENT>0000899243-19-024081.txt : 20190923
<SEC-HEADER>0000899243-19-024081.hdr.sgml : 20190923
<ACCEPTANCE-DATETIME>20190923214511
ACCESSION NUMBER:		0000899243-19-024081
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190919
FILED AS OF DATE:		20190923
DATE AS OF CHANGE:		20190923

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TULLIS JAMES L L
		CENTRAL INDEX KEY:			0001230641

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39049
		FILM NUMBER:		191109082

	MAIL ADDRESS:	
		STREET 1:		100 FIRST STAMFORD PLACE
		CITY:			STAMFORD
		STATE:			CT
		ZIP:			06907

ISSUER:		

	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
		FISCAL YEAR END:			1231

	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>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
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                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F11"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series H Redeemable Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F12"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-09-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>742761</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F12"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F12"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F12"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4045</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series H Redeemable Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F12"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-09-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>58359932</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F12"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F12"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F12"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>317804</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F13"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The shares reported on this form are held of record by Tullis-Dickerson Capital Focus III, L.P. (&quot;Tullis&quot;), Tullis Growth Fund, L.P. (&quot;Tullis Growth&quot;) and Tullis Growth Fund II, L.P. (&quot;Tullis Growth II&quot;). Tullis-Dickerson Partners III, LLC (&quot;Tullis Partners&quot;) is the general partner of Tullis and may be deemed to beneficially own the securities held by Tullis. Tullis Growth Partners, LLC and Tullis Growth Partners II, LLC are the general partners of Tullis Growth and Tullis Growth II, respectively, and may be deemed to beneficially own the securities held by Tullis Growth and Tullis Growth II. James L.L. Tullis is a Principal of each of the foregoing entities and may be deemed to possess voting and investment control over, and may be deemed to have an indirect beneficial ownership with respect to, the shares held by Tullis, Tullis Growth and Tullis Growth II.</footnote>
        <footnote id="F2">Represents securities held of record by Tullis.</footnote>
        <footnote id="F3">The warrants are currently exercisable and will terminate upon closing of the Issuer's initial public offering.</footnote>
        <footnote id="F4">Represents warrants that previously entitled the holders to purchase Series E Redeemable Convertible Preferred Stock, which, pursuant to their terms, were settled in shares of the Issuer's Common Stock.</footnote>
        <footnote id="F5">Includes warrants held by Tullis and Tullis Growth, respectively, to purchase 43 shares of the Issuer's Common Stock and warrants to purchase 11,455 shares of the Issuer's Common Stock.</footnote>
        <footnote id="F6">The Series A-3 Redeemable Convertible Preferred Stock (the &quot;Series A-3&quot;) is convertible into the Issuer's Common Stock on a 183.635-for-one basis at the holder's election and has no expiration date. The Series A-3 automatically converted into Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F7">The Series C Redeemable Convertible Preferred Stock (the &quot;Series C&quot;) is convertible into the Issuer's Common Stock on a 57.294-for-one basis at the holder's election and has no expiration date. The Series C automatically converted into Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F8">The Series E Redeemable Convertible Preferred Stock (the &quot;Series E&quot;) is convertible into the Issuer's Common Stock on a 57.294-for-one basis at the holder's election and has no expiration date. The Series E automatically converted into Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F9">Includes 656,282 and 273,150 shares of common stock underlying the Series E shares held by Tullis and Tullis Growth, respectively.</footnote>
        <footnote id="F10">The Series F Redeemable Convertible Preferred Stock (&quot;Series F&quot;) is convertible into the Issuer's Common Stock on a 183.635-for-one basis at the holder's election and has no expiration date. The Series F automatically converted into Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F11">Includes 242,226 and 199,771 shares of common stock underlying the Series F shares held by Tullis and Tullis Growth, respectively.</footnote>
        <footnote id="F12">The Series H Redeemable Convertible Preferred Stock (&quot;Series H&quot;) is convertible into the Issuer's Common Stock on a 183.635-for-one basis at the holder's election and has no expiration date. The Series H automatically converted into Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F13">Includes 106,897 shares, 105,453 shares and 105,453 shares of common stock underlying the Series H shares held by Tullis, Tullis Growth and Tullis Growth II, respectively.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James L.L. Tullis</signatureName>
        <signatureDate>2019-09-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
