<SEC-DOCUMENT>0001231919-26-000124.txt : 20260209
<SEC-HEADER>0001231919-26-000124.hdr.sgml : 20260209
<ACCEPTANCE-DATETIME>20260209181916
ACCESSION NUMBER:		0001231919-26-000124
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260209
FILED AS OF DATE:		20260209
DATE AS OF CHANGE:		20260209

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Atlas Venture Fund X, L.P.
		CENTRAL INDEX KEY:			0001628098
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612862

	BUSINESS ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ATLAS VENTURE ASSOCIATES X, L.P.
		CENTRAL INDEX KEY:			0001742766
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612861

	BUSINESS ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQ.
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQ.
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Atlas Venture Associates X, LLC
		CENTRAL INDEX KEY:			0001742765
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612860

	BUSINESS ADDRESS:	
		STREET 1:		400 TECH. SQ.
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECH. SQ.
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Atlas Venture Associates Opportunity I, LLC
		CENTRAL INDEX KEY:			0001780066
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612857

	BUSINESS ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Atlas Venture Opportunity Fund I, L.P.
		CENTRAL INDEX KEY:			0001759241
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612859

	BUSINESS ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE, 10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE, 10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Atlas Venture Associates Opportunity I, L.P.
		CENTRAL INDEX KEY:			0001780065
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		26612858

	BUSINESS ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-201-2700

	MAIL ADDRESS:	
		STREET 1:		400 TECHNOLOGY SQUARE
		STREET 2:		10TH FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Generation Bio Co.
		CENTRAL INDEX KEY:			0001733294
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				814301284
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		301 BINNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		857-529-5908

	MAIL ADDRESS:	
		STREET 1:		301 BINNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
</SEC-HEADER>
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            <rptOwnerStreet2></rptOwnerStreet2>
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    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001759241</rptOwnerCik>
            <rptOwnerName>Atlas Venture Opportunity Fund I, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>300 TECHNOLOGY SQUARE, 8TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02139</rptOwnerZipCode>
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        </reportingOwnerId>
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            <rptOwnerStreet1>300 TECHNOLOGY SQUARE, 8TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02139</rptOwnerZipCode>
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            <rptOwnerStreet1>300 TECHNOLOGY SQUARE, 8TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02139</rptOwnerZipCode>
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    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>U</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>711193</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
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                    <value>D</value>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-02-09</value>
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                <transactionFormType>4</transactionFormType>
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            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>116693</value>
                </transactionShares>
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                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>0</value>
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            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <value>2026-02-09</value>
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            <transactionAmounts>
                <transactionShares>
                    <value>60</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
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                    <value>D</value>
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                    <value>0</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                    <value>See footnote</value>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the terms of that certain Agreement and Plan of Merger (the &quot;Merger Agreement&quot;), by and among Generation Bio. Co. (the &quot;Issuer&quot;), XOMA Royalty Corporation (&quot;Parent&quot;) and Parent's wholly-owned subsidiary, XRA 7 Corp. (&quot;Merger Sub&quot;), dated as of December 15, 2025, the shares (the &quot;Shares&quot;) of common stock, par value $0.0001 per share, of the Issuer (the &quot;Common Stock&quot;) that were tendered to Merger Sub prior to the expiration time of the offer were exchanged for (i) a purchase price of $4.2913 per
Share to the stockholders in cash, without interest and less any applicable tax withholding (the &quot;Cash Amount&quot;), plus (ii) one non-tradeable contingent value right per Share (the &quot;CVR&quot;),</footnote>
        <footnote id="F2">(continued from footnote 1) which represents the right to receive certain contingent payments in cash in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent, with an estimated maximum contingent consideration amount of $25.01 per CVR (the Cash Amount plus one CVR, collectively, the &quot;Offer Price&quot;). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Merger Sub merged with and into the Issuer,
effective as of February 9, 2026 (the &quot;Effective Time&quot;), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent.</footnote>
        <footnote id="F3">The shares are held directly by Atlas Venture Fund X, L.P. (&quot;Atlas Venture Fund X&quot;). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. (&quot;AVA X LP&quot;). Atlas Venture Associates X, LLC (&quot;AVA X LLC&quot;) is the general partner of AVA X LP. Each of AVA X LP and AVA X LLC disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Fund X, except to the extent of its pecuniary interest therein, if any.</footnote>
        <footnote id="F4">The shares are held directly by Atlas Venture Opportunity Fund I, L.P. (&quot;Atlas Venture Opportunity Fund I&quot;). The general partner of Atlas Venture Opportunity Fund I is Atlas Venture Associates Opportunity I, LP (&quot;AVAO I LP&quot;). Atlas Venture Associates Opportunity I, LLC (&quot;AVAO I LLC&quot;) is the general partner of AVAO I LP. Each of AVAO I LP and AVAO I LLC disclaims Section 16 beneficial ownership of the securities held by Atlas Venture Opportunity Fund I, except to the extent of its pecuniary interest therein, if any.</footnote>
        <footnote id="F5">The shares are held directly by AVAO I LP. AVAO I LLC is the general partner of AVAO I LP. AVAO I LLC disclaims Section 16 beneficial ownership of the securities held by AVAO I LP except to the extent of its pecuniary interest therein, if any.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Atlas Venture Fund X, L.P., By: Atlas Venture Associates X, L.P., Its: General Partner, By: Atlas Venture Associates X, LLC, Its: General Partner, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates X, L.P., By: Atlas Venture Associates X, LLC, Its: General Partner, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates X, LLC, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Opportunity Fund I, L.P., By: Atlas Venture Associates Opportunity I, L.P., Its general partner, By: Atlas Venture Associates Opportunity I, LLC, Its general partner, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates Opportunity I, L.P., By: Atlas Venture Associates Opportunity I, LLC, Its general partner, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates Opportunity I, LLC, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2026-02-09</signatureDate>
    </ownerSignature>
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