<SEC-DOCUMENT>0001872398-26-000002.txt : 20260303
<SEC-HEADER>0001872398-26-000002.hdr.sgml : 20260303
<ACCEPTANCE-DATETIME>20260303184850
ACCESSION NUMBER:		0001872398-26-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260301
FILED AS OF DATE:		20260303
DATE AS OF CHANGE:		20260303

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Chung Jane
		CENTRAL INDEX KEY:			0001872398
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38662
		FILM NUMBER:		26717637

	MAIL ADDRESS:	
		STREET 1:		C/O SUTRO BIOPHARMA, INC.
		STREET 2:		310 UTAH AVE., SUITE 150
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SUTRO BIOPHARMA, INC.
		CENTRAL INDEX KEY:			0001382101
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				452441988
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		111 OYSTER POINT BLVD.
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		650-392-8412

	MAIL ADDRESS:	
		STREET 1:		111 OYSTER POINT BLVD.
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SUTRO BIOPHARMA INC
		DATE OF NAME CHANGE:	20061127
</SEC-HEADER>
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<SEQUENCE>1
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    <periodOfReport>2026-03-01</periodOfReport>

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        <issuerCik>0001382101</issuerCik>
        <issuerName>SUTRO BIOPHARMA, INC.</issuerName>
        <issuerTradingSymbol>STRO</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>Chung Jane</rptOwnerName>
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            <rptOwnerStreet2>111 OYSTER POINT BLVD.</rptOwnerStreet2>
            <rptOwnerCity>SOUTH SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94080</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
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        </nonDerivativeTransaction>
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    <derivativeTable>
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            <securityTitle>
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            </securityTitle>
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            <transactionDate>
                <value>2026-03-01</value>
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                <transactionPricePerShare>
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            <exerciseDate>
                <footnoteId id="F3"/>
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            <expirationDate>
                <value>2027-03-01</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
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                    <value>688</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            <expirationDate>
                <value>2028-03-01</value>
            </expirationDate>
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                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                <directOrIndirectOwnership>
                    <value>D</value>
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                <transactionCode>A</transactionCode>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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                    <value></value>
                </natureOfOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>20.55</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-03-02</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>175000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
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                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2036-03-02</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>175000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
                    <value>175000</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
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    <footnotes>
        <footnote id="F1">Represents the number of shares of Common Stock that have been withheld by the Issuer to satisfy its income tax withholding and remittance obligations in connection with the net settlement of restricted stock units; does not represent a sale by the reporting person.</footnote>
        <footnote id="F2">Each RSU represents a contingent right to receive one (1) share of the Issuer's Common Stock upon settlement.</footnote>
        <footnote id="F3">The RSUs vested or vest as to 1/4 of the total award annually, with the first tranche vested on March 1, 2024, subject to continued service through each vesting date.</footnote>
        <footnote id="F4">The RSUs vested or vest as to 1/4 of the total award annually, with the first tranche vested on March 1, 2025, subject to continued service through each vesting date.</footnote>
        <footnote id="F5">The RSUs vested or vest as to 1/4 of the total award annually, with the first tranche vested on March 2, 2026, subject to continued service through each vesting date.</footnote>
        <footnote id="F6">The RSUs shall vest as to 1/4 of the total award annually, with the first tranche vesting on March 1, 2027, subject to continued service through each vesting date.</footnote>
        <footnote id="F7">1/48 of the total option award shall vest monthly, subject to the reporting person's continued service through each vesting date, with the first tranche vesting on April 1, 2026.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ David Pauling as attorney-in-fact</signatureName>
        <signatureDate>2026-03-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</DOCUMENT>
</SEC-DOCUMENT>
