<SEC-DOCUMENT>0001209191-21-042857.txt : 20210623
<SEC-HEADER>0001209191-21-042857.hdr.sgml : 20210623
<ACCEPTANCE-DATETIME>20210623202627
ACCESSION NUMBER:		0001209191-21-042857
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210621
FILED AS OF DATE:		20210623
DATE AS OF CHANGE:		20210623

REPORTING-OWNER:	

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

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		211040208

	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
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		211040207

	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
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		211040205

	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 Opportunity I, L.P.
		CENTRAL INDEX KEY:			0001780065
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39319
		FILM NUMBER:		211040206

	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]
		IRS NUMBER:				814301281
		STATE OF INCORPORATION:			DE
		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
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                <transactionShares>
                    <value>53</value>
                    <footnoteId id="F6"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.69</value>
                    <footnoteId id="F11"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>666</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares were sold pursuant to a Rule 10b5-1 trading plan dated April 20 ,2021.</footnote>
        <footnote id="F2">The shares reported herein give effect to the pro rata distribution of shares by Atlas Venture Fund X, L.P. for no additional consideration to its limited partners and its and general partner, Atlas Venture Associates X, L.P. (&quot;AVA X LP&quot;), subsequent to the Reporting Persons' last Section 16 filing reporting ownership of the Issuer's Common Stock. As the distribution of such shares constituted only a change in the form of the Reporting Persons' ownership in such shares, the Reporting Persons were not required to report the distribution pursuant to Section 16.</footnote>
        <footnote id="F3">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.08 to $25.07 inclusive. The Reporting Persons undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (3), (5), (8), (9), (10) and (11).</footnote>
        <footnote id="F4">The shares are held directly by AVA X LP. Atlas Venture Associates X, LLC (&quot;AVA X LLC&quot;) is the general partner of AVA X LP. AVA X LLC disclaims Section 16 beneficial ownership of the securities held by AVA X LP except to the extent of its pecuniary interest therein, if any.</footnote>
        <footnote id="F5">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.08 to $25.20 inclusive.</footnote>
        <footnote id="F6">The shares reported herein give effect to the pro rata distribution of shares by Atlas Venture Opportunity Fund I, L.P. for no additional consideration to its limited partners and its and general partner, Atlas Venture Associates Opportunity I, LP (&quot;AVAO LP&quot;), subsequent to the Reporting Persons' last Section 16 filing reporting ownership of the Issuer's Common Stock. As the distribution of such shares constituted only a change in the form of the Reporting Persons' ownership in such shares, the Reporting Persons were not required to report the distribution pursuant to Section 16.</footnote>
        <footnote id="F7">The shares are held directly by AVAO LP. Atlas Venture Associates Opportunity I, LLC (&quot;AVAO LLC&quot;) is the general partner of AVAO LP. AVAO LLC disclaims Section 16 beneficial ownership of the securities held by AVAO LP except to the extent of its pecuniary interest therein, if any.</footnote>
        <footnote id="F8">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.08 to $25.07 inclusive.</footnote>
        <footnote id="F9">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.10 to $25.285 inclusive.</footnote>
        <footnote id="F10">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.63 to $25.62 inclusive.</footnote>
        <footnote id="F11">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.63 to $25.95 inclusive.</footnote>
    </footnotes>

    <remarks></remarks>

    <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>2021-06-23</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates X, LLC, By: /s/ Ommer Chohan, Chief Financial Officer</signatureName>
        <signatureDate>2021-06-23</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates Opportunity I, L.P., By: Atlas Venture Associates Opportunity I, LLC, its general partner, By: Ommer Chohan, Chief Financial Officer, /s/ Ommer Chohan</signatureName>
        <signatureDate>2021-06-23</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Atlas Venture Associates Opportunity I, LLC, By: Ommer Chohan, Chief Financial Officer, /s/ Ommer Chohan</signatureName>
        <signatureDate>2021-06-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
