CUSIP
No. 37148K100
|
Page
2 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Fund X, L.P.
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
10,111,9391
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
10,111,9391
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
10,111,9391
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
21.7%2
|
12.
|
Type
of Reporting Person (See Instructions)
PN
|
(1)
As described in Item 4 below, Atlas Venture Fund X, L.P., a Delaware limited partnership (“Atlas X”), Atlas Venture
Associates X, L.P., a Delaware limited partnership (“AVA X LP”) and Atlas Venture Associates X, LLC, a Delaware limited
liability company (“AVA X LLC” and together with Atlas X and AVA X LP, the “Fund X Reporting Persons”)
beneficially own 10,111,939 shares of the Issuer’s Common Stock. All of these shares are directly held by Atlas X. AVA X
LP is the general partner of Atlas X and AVA X LLC is the general partner of AVA X LP. Each of AVA X LP and AVA X LLC has voting
and dispositive power over the shares held by Atlas X. As such, each of the Fund X Reporting Persons share voting and dispositive
power with respect to the shares held by Atlas X.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
3 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Associates X, L.P.
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
10,111,9391
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
10,111,9391
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
10,111,9391
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
21.7%2
|
12.
|
Type
of Reporting Person (See Instructions)
PN
|
(1)
As described in Item 4 below, Atlas Venture Fund X, L.P., a Delaware limited partnership (“Atlas X”), Atlas Venture
Associates X, L.P., a Delaware limited partnership (“AVA X LP”) and Atlas Venture Associates X, LLC, a Delaware limited
liability company (“AVA X LLC” and together with Atlas X and AVA X LP, the “Fund X Reporting Persons”)
beneficially own 10,111,939 shares of the Issuer’s Common Stock. All of these shares are directly held by Atlas X. AVA X
LP is the general partner of Atlas X and AVA X LLC is the general partner of AVA X LP. Each of AVA X LP and AVA X LLC has voting
and dispositive power over the shares held by Atlas X. As such, each of the Fund X Reporting Persons share voting and dispositive
power with respect to the shares held by Atlas X.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
4 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Associates X, LLC
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
10,111,9391
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
10,111,9391
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
10,111,9391
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
21.7%2
|
12.
|
Type
of Reporting Person (See Instructions)
OO
|
(1)
As described in Item 4 below, Atlas Venture Fund X, L.P., a Delaware limited partnership (“Atlas X”), Atlas Venture
Associates X, L.P., a Delaware limited partnership (“AVA X LP”) and Atlas Venture Associates X, LLC, a Delaware limited
liability company (“AVA X LLC” and together with Atlas X and AVA X LP, the “Fund X Reporting Persons”)
beneficially own 10,111,939 shares of the Issuer’s Common Stock. All of these shares are directly held by Atlas X. AVA X
LP is the general partner of Atlas X and AVA X LLC is the general partner of AVA X LP. Each of AVA X LP and AVA X LLC has voting
and dispositive power over the shares held by Atlas X. As such, each of the Fund X Reporting Persons share voting and dispositive
power with respect to the shares held by Atlas X.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
5 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Opportunity Fund I, L.P.
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
1,366,9371
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
1,366,9371
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,366,9371
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
2.9%2
|
12.
|
Type
of Reporting Person (See Instructions)
PN
|
(1)
As described in Item 4 below, Atlas Venture Opportunity Fund I, L.P., a Delaware limited partnership (“AVO I”), Atlas
Venture Associates Opportunity I, L.P., a Delaware limited partnership (“AVAO LP”) and Atlas Venture Associates Opportunity
I, LLC, a Delaware limited liability company (“AVAO LLC” and together with AVO I and AVAO LP, the “Opportunity
Fund Reporting Persons”) beneficially own 1,366,937 shares of the Issuer’s Common Stock. All of these shares are directly
held by AVO I. AVAO LP is the general partner of AVO I and AVAO LLC is the general partner of AVAO LP. Each of AVAO LP and AVAO
LLC has voting and dispositive power over the shares held by AVO I. As such, each of the Opportunity Fund Reporting Persons share
voting and dispositive power with respect to the shares held by AVO I.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
6 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Associates Opportunity I, L.P.
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
1,366,9371
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
1,366,9371
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,366,9371
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
2.9%2
|
12.
|
Type
of Reporting Person (See Instructions)
PN
|
(1)
As described in Item 4 below, Atlas Venture Opportunity Fund I, L.P., a Delaware limited partnership (“AVO I”), Atlas
Venture Associates Opportunity I, L.P., a Delaware limited partnership (“AVAO LP”) and Atlas Venture Associates Opportunity
I, LLC, a Delaware limited liability company (“AVAO LLC” and together with AVO I and AVAO LP, the “Opportunity
Fund Reporting Persons”) beneficially own 1,366,937 shares of the Issuer’s Common Stock. All of these shares are directly
held by AVO I. AVAO LP is the general partner of AVO I and AVAO LLC is the general partner of AVAO LP. Each of AVAO LP and AVAO
LLC has voting and dispositive power over the shares held by AVO I. As such, each of the Opportunity Fund Reporting Persons share
voting and dispositive power with respect to the shares held by AVO I.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
7 of 10 Pages
|
1.
|
Name
of Reporting Persons
Atlas
Venture Associates Opportunity I, LLC
|
2.
|
Check
the Appropriate Box if a Member of a Group (See Instructions)
(a)
☐
(b)
☒
|
3.
|
SEC
USE ONLY
|
4.
|
Citizenship
or Place of Organization
Delaware
|
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With:
|
5.
|
Sole
Voting Power
0
|
6.
|
Shared
Voting Power
1,366,9371
|
7.
|
Sole
Dispositive Power
0
|
8.
|
Shared
Dispositive Power
1,366,9371
|
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,366,9371
|
10.
|
Check
if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
|
11.
|
Percent
of Class Represented by Amount in Row (9)
2.9%2
|
12.
|
Type
of Reporting Person (See Instructions)
OO
|
(1)
As described in Item 4 below, Atlas Venture Opportunity Fund I, L.P., a Delaware limited partnership (“AVO I”), Atlas
Venture Associates Opportunity I, L.P., a Delaware limited partnership (“AVAO LP”) and Atlas Venture Associates Opportunity
I, LLC, a Delaware limited liability company (“AVAO LLC” and together with AVO I and AVAO LP, the “Opportunity
Fund Reporting Persons”) beneficially own 1,366,937 shares of the Issuer’s Common Stock. All of these shares are directly
held by AVO I. AVAO LP is the general partner of AVO I and AVAO LLC is the general partner of AVAO LP. Each of AVAO LP and AVAO
LLC has voting and dispositive power over the shares held by AVO I. As such, each of the Opportunity Fund Reporting Persons share
voting and dispositive power with respect to the shares held by AVO I.
(2)
This percentage is calculated based upon 46,516,475 outstanding shares of Common Stock of the Issuer as of November 30, 2020,
as reported in the Issuer’s prospectus and filed with the Securities and Exchange Commission on January 7, 2021.
CUSIP
No. 37148K100
|
Page
8 of 10 Pages
|
Generation
Bio Co. (the “Issuer”)
Item
1(b)
|
Address
of Issuer's Principal Executive Offices
|
301
Binney Street
Cambridge, MA, 02142
Item
2(a)
|
Name
of Person Filing
|
This
Schedule 13G is filed by (i) Atlas Venture Fund X, L.P., a Delaware limited partnership (“Atlas X”), (ii) Atlas Venture
Associates X, L.P., a Delaware limited partnership (“AVA X LP”), (iii) Atlas Venture Associates X, LLC, a Delaware
limited liability company (“AVA X LLC” and together with Atlas X and AVA X LP, the “Fund X Reporting Persons”),
(iv) Atlas Venture Opportunity Fund I, L.P., a Delaware limited partnership (“AVO I”), (v) Atlas Venture Associates
Opportunity I, L.P., a Delaware limited partnership (“AVAO LP”) and (vi) Atlas Venture Associates Opportunity I, LLC,
a Delaware limited liability company (“AVAO LLC” and together with AVO I and AVAO LP, the “Opportunity Fund
Reporting Persons” and together with the Fund X Reporting Persons, the "Reporting Persons”).
Item
2(b)
|
Address
of Principal Business Office or, if none, Residence
|
300
Technology Square, 8th Floor
Cambridge, Massachusetts 02139
Each
of Atlas X, AVA X LP, AVO I and AVAO LP is a Delaware limited partnership. Each of AVA X LLC and AVAO LLC is a Delaware limited
liability company.
Item
2(d)
|
Title
of Class of Securities
|
Common
Stock, $0.0001 par value per share
37148K100
Item
3
Not
applicable.
Provide
the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in
Item 1
(a)
Amount beneficially owned: Atlas X is the record owner of 10,111,939 shares of Common Stock. AVA X LP is the general partner of
Atlas X and AVA X LLC is the general partner of AVA X LP. Each of Atlas X, AVA X LP and AVA X LLC has shared voting and dispositive
power over the shares held by Atlas X. As such, each of Atlas X, AVA X LP and AVA X LLC may be deemed to beneficially own the
shares held by Atlas X.
Amount
beneficially owned: AVO I is the record owner of 1,366,937 shares of Common Stock. AVAO LP is the general partner of AVO I and
AVAO LLC is the general partner of AVAO LP. Each of AVO I, AVAO LP and AVAO LLC has shared voting and dispositive power over the
shares held by AVO I. As such, each of AVO I, AVAO LP and AVAO LLC may be deemed to beneficially own the shares held by AVO I.
(b)
Percent of class: Fund X Reporting Persons and Opportunity Fund Reporting Persons may be deemed to beneficially own 21.7% and
2.9%, respectively, of the Issuer’s outstanding Common Stock, which percentages are calculated based upon 46,516,475 outstanding
shares of Common Stock of the Issuer as of November 30, 2020, as reported in the Issuer’s prospectus and filed with the
Securities and Exchange Commission on January 7, 2021.
CUSIP No. 37148K100
|
Page
9 of 10 Pages
|
Collectively,
the Reporting Persons beneficially own an aggregate of 11,478,876 shares of Common Stock, which represents 24.7% of the Issuer's
outstanding Common Stock. The Fund X Reporting Persons and the Opportunity Fund Reporting Persons are under common control and
as a result, the Reporting Persons may be deemed to be members of a group. However, the Reporting Persons disclaim such group
membership, and this Schedule 13G shall not be deemed an admission that the Reporting Persons are members of a group for purposes
of Section 13 or for any other purposes.
(c)
Number of shares as to which the person has:
(i)
Sole power to vote or to direct the vote: None of the Reporting Persons have the sole power to direct the vote of the Common Stock.
(ii)
Shared power to vote or to direct the vote: Each Fund X Reporting Person shares power to vote or direct the vote of 10,111,939
shares of Common Stock and each Opportunity Fund Reporting Person shares power to vote or direct the vote of 1,366,937 shares
of Common Stock.
(iii)
Sole power to dispose or to direct the disposition of: None of the Reporting Persons have the sole power to dispose or to direct
the disposition of the Common Stock.
(iv)
Shared power to dispose or to direct the disposition of: Each Fund X Reporting Person shares power to dispose or to direct the
disposition of 10,111,939 shares of Common Stock and each Opportunity Fund Reporting Person shares power to dispose or to direct
the disposition of 1,366,937 shares of Common Stock.
Item
5
|
Ownership
of Five Percent or Less of a Class
|
If
this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial
owner of more than five percent of the class of securities, check the following.☐
Item
6
|
Ownership
of More than Five Percent of Another Person
|
Not
applicable.
Item
7
|
Identification
and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company
|
Not
applicable.
Item
8
|
Identification
and Classification of Members of the Group
|
Not
applicable.
Item
9
|
Notice
of Dissolution of Group
|
Not
applicable.
Not
applicable.
CUSIP
No. 37148K100
|
Page
10 of 10 Pages
|
SIGNATURE
After
reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true,
complete and correct.
Dated:
February 16, 2021
|
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
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES X, L.P.
|
|
By:
Atlas Venture Associates X, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES X, LLC
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE OPPORTUNITY FUND I, L.P.
|
|
By:
Atlas Venture Associates Opportunity I, L.P., its general partner
|
|
By:
Atlas Venture Associates X, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES OPPORTUNITY I, L.P.
|
|
By:
Atlas Venture Associates Opportunity I, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES OPPORTUNITY I, LLC
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
EXHIBITS
A:
|
Joint
Filing Agreement
|
Exhibit
A
JOINT
FILING AGREEMENT
In
accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing
on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the Common Stock of Generation
Bio Co. and further agree that this agreement be included as an exhibit to such filing. Each party to the agreement expressly
authorizes each other party to file on its behalf any and all amendments to such statement. Each party to this agreement agrees
that this joint filing agreement may be signed in counterparts.
IN
WITNESS WHEREOF, the undersigned have executed this Joint Filing Agreement as of February 16, 2021.
|
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
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES X, L.P.
|
|
By:
Atlas Venture Associates X, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES X, LLC
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE OPPORTUNITY FUND I, L.P.
|
|
By:
Atlas Venture Associates Opportunity I, L.P., its general partner
|
|
By:
Atlas Venture Associates X, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES OPPORTUNITY I, L.P.
|
|
By:
Atlas Venture Associates Opportunity I, LLC, its general partner
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|
|
ATLAS
VENTURE ASSOCIATES OPPORTUNITY I, LLC
|
|
By:
|
/s/
Ommer Chohan
|
|
|
Name:
|
Ommer
Chohan
|
|
|
Title:
|
CFO
|
|