<SEC-DOCUMENT>0000950170-25-076571.txt : 20250522
<SEC-HEADER>0000950170-25-076571.hdr.sgml : 20250522
<ACCEPTANCE-DATETIME>20250522193747
ACCESSION NUMBER:		0000950170-25-076571
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250520
FILED AS OF DATE:		20250522
DATE AS OF CHANGE:		20250522

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lang Matthew
		CENTRAL INDEX KEY:			0001712069
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-42489
		FILM NUMBER:		25978813

	MAIL ADDRESS:	
		STREET 1:		C/O MYOVANT SCIENCES INC.
		STREET 2:		2000 SIERRA POINT PARKWAY, 9TH FLOOR
		CITY:			BRISBANE
		STATE:			CA
		ZIP:			94005

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Metsera, Inc.
		CENTRAL INDEX KEY:			0002040807
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3 WORLD TRADE CENTER
		STREET 2:		175 GREENWICH STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10007
		BUSINESS PHONE:		(212) 784-6595

	MAIL ADDRESS:	
		STREET 1:		3 WORLD TRADE CENTER
		STREET 2:		175 GREENWICH STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10007
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>ownership.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-05-20</periodOfReport>

    <issuer>
        <issuerCik>0002040807</issuerCik>
        <issuerName>Metsera, Inc.</issuerName>
        <issuerTradingSymbol>MTSR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001712069</rptOwnerCik>
            <rptOwnerName>Lang Matthew</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O METSERA, INC., 3 WORLD TRADE CENTER</rptOwnerStreet1>
            <rptOwnerStreet2>175 GREENWICH STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10007</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Legal Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>29.25</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-05-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>46875</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2035-05-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>46875</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46875</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The options will vest and become exercisable in 48 substantially equal monthly installments after the date of grant, such that the option will be vested in full on the fourth anniversary of the date of grant, subject to the Reporting Person's continued service through each such vesting date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Matthew Lang</signatureName>
        <signatureDate>2025-05-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
