<SEC-DOCUMENT>0001171843-26-002893.txt : 20260430
<SEC-HEADER>0001171843-26-002893.hdr.sgml : 20260430
<ACCEPTANCE-DATETIME>20260430160025
ACCESSION NUMBER:		0001171843-26-002893
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260429
FILED AS OF DATE:		20260430
DATE AS OF CHANGE:		20260430

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Anderman Jonathan
		CENTRAL INDEX KEY:			0002032625
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39696
		FILM NUMBER:		26924767

	MAIL ADDRESS:	
		STREET 1:		COMPASS THERAPEUTICS, INC.
		STREET 2:		80 GUEST STREET, SUITE 601
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02135

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Compass Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001738021
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		80 GUEST STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02135
		BUSINESS PHONE:		617-500-8099

	MAIL ADDRESS:	
		STREET 1:		80 GUEST STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02135

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Olivia Ventures, Inc.
		DATE OF NAME CHANGE:	20180419
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>ownership.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2026-04-29</periodOfReport>

    <dateOfOriginalSubmission>2026-04-29</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001738021</issuerCik>
        <issuerName>Compass Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>CMPX</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002032625</rptOwnerCik>
            <rptOwnerName>Anderman Jonathan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O COMPASS THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>80 GUEST STREET, SUITE 601</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02135</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>General Counsel</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-04-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.89</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>196000</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">150,000 of the shares represents unvested restricted stock units (&quot;RSU&quot;) granted on January 2, 2026. Each RSU represents a contingent right to receive one share of common stock. The award is subject to service-based vesting conditions and vests in four equal annual installments, with the first installment vested on January 2, 2027.</footnote>
    </footnotes>

    <remarks>Explanatory Note: This amendment is being filed to correct the transaction code reported in Table I of the original Form 4 filed on April 29, 2026. The transaction was inadvertently reported using transaction code A. The correct transaction code is P, which reflects that the transaction was an open market purchase. All other information in the original filing remains unchanged.</remarks>

    <ownerSignature>
        <signatureName>/s/ Neil Lerner attorney-in-fact</signatureName>
        <signatureDate>2026-04-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
