<SEC-DOCUMENT>0001193125-25-280814.txt : 20251113
<SEC-HEADER>0001193125-25-280814.hdr.sgml : 20251113
<ACCEPTANCE-DATETIME>20251113212007
ACCESSION NUMBER:		0001193125-25-280814
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251113
FILED AS OF DATE:		20251113
DATE AS OF CHANGE:		20251113

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Marso Steven
		CENTRAL INDEX KEY:			0002043242
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-42489
		FILM NUMBER:		251480728

	MAIL ADDRESS:	
		STREET 1:		C/O METSERA, INC.
		STREET 2:		1200 MORRIS TURNPIKE, SUITE 3005
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

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
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<DESCRIPTION>4
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        <issuerCik>0002040807</issuerCik>
        <issuerName>Metsera, Inc.</issuerName>
        <issuerTradingSymbol>MTSR</issuerTradingSymbol>
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            <rptOwnerName>Marso Steven</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O METSERA, INC. 3 WORLD TRADE</rptOwnerStreet1>
            <rptOwnerStreet2>CENTER 175 GREENWICH STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10007</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>CHIEF MEDICAL OFFICER</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <equitySwapInvolved>false</equitySwapInvolved>
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                <footnoteId id="F2"/>
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                <value>2035-05-19</value>
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            <expirationDate>
                <value>2033-05-25</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the Agreement and Plan of Merger dated September 21, 2025, as amended on November 7, 2025 (the &quot;Merger Agreement&quot;), by and among Metsera, Inc. (the &quot;Company&quot;), Pfizer Inc., a Delaware corporation (&quot;Parent&quot;), and Mayfair Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of the Parent (the &quot;Merger Sub&quot;), the Merger Sub merged with and into the Company, with the Company continuing as the surviving corporation and a wholly owned subsidiary of the Parent (the &quot;Merger&quot;).  At the Effective Time of the Merger (as defined in the Merger Agreement), each issued and outstanding share of common stock, par value $0.00001 per share of the Company (the &quot;Common Stock&quot;) was converted automatically into the right to receive (i) cash in an amount equal to $65.60 per share without interest (the &quot;Closing Amount&quot;), net of all applicable withholding taxes, plus</footnote>
        <footnote id="F2">(Continued from footnote 1) (ii) one contractual contingent value right representing the right to receive contingent payments (a &quot;CVR&quot;) in cash, without interest, upon the achievement of certain specified milestones, in accordance with the terms and conditions of the contingent value rights agreement entered into by the Parent and Equiniti Trust Company, LLC, dated November 13, 2025 (collectively, the &quot;Merger Consideration&quot;).</footnote>
        <footnote id="F3">Pursuant to the Merger Agreement, each outstanding and unexercised option immediately prior to the Effective Time, whether vested or unvested, was cancelled in exchange for the right to receive (x) an amount in cash equal to the product of (i) the excess, if any, of the Closing Amount minus the exercise price of such option, multiplied by (ii) the number of shares of Common Stock subject to such option immediately prior to the Effective Time, net of all applicable withholding taxes, and (y) one CVR for each share of the Common Stock subject to such stock option immediately prior to the Effective Time.  In the case of any unvested stock options, the cash payment and the CVRs are subject to the same vesting schedule terms as were applicable to the stock options,</footnote>
        <footnote id="F4">(Continued from footnote 3) except that all such payments will become vested upon the first anniversary of the closing of the Merger, subject to the holder's continued service with the Parent or its subsidiaries through the first anniversary of the Merger.</footnote>
        <footnote id="F5">On November 12, 2025, the Reporting Person was granted restricted stock units (&quot;RSUs&quot;) under the Company's 2025 Incentive Award Plan in a transaction exempt under Rule 16b-3. Each RSU represents a contingent right to receive one share of Common Stock.  The RSUs vest in 36 substantially equal monthly installments from November 12, 2025.  Pursuant to the Merger Agreement, all RSUs were cancelled and converted into the right to receive (x) an amount of cash equal to the Closing Amount multiplied by the number of shares of Common Stock subject to such RSU immediately prior to the Effective Time, net of all applicable withholding taxes, and (y) a number of CVRs equal to the under of the shares of Common Stock underlying the RSU.  The cash payment and the CVRs are subject to the same vesting schedule terms as were applicable to the RSUs.</footnote>
        <footnote id="F6">This option provided for vesting in 48 substantially equal monthly installments from May 20, 2025.</footnote>
        <footnote id="F7">This option was fully vested as to 75% of the shares underlying the option and 25% was to be vested on May 26, 2026.</footnote>
        <footnote id="F8">This option was fully vested.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Matthew Lang, Attorney-in-Fact for Steven Marso</signatureName>
        <signatureDate>2025-11-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
