SEC FORM 3

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

MCDONOUGH GEOFF

(Last)

(First)

(Middle)

C/O GENERATION BIO CO.,

301 BINNEY STREET

(Street)

CAMBRIDGE

02142

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
06/11/2020

3. Issuer Name and Ticker or Trading Symbol
Generation Bio Co. [ GBIO ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
X	Officer (give title below)		Other (specify below)
	See Remarks

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	1,365,849	D
Common Stock	226,462	I	See Footnote⁽¹⁾

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	113,231	⁽²⁾	D
Stock Option (right to buy)	⁽³⁾	03/04/2030	Common Stock	199,038	$2.92	D
Stock Option (right to buy)	⁽⁴⁾	03/04/2030	Common Stock	199,038	$2.92	D

Explanation of Responses:

1. The securities are directly held by the McDonough Family 2018 Irrevocable Trust, or the Trust. The reporting person is the settlor of the Trust, Allison L. McDonough and David S. Grayzel are trustees for the Trust and the Trust is for the benefit of Graeme and Owen McDonough. The reporting person may be deemed to beneficially own the shares of common stock owned by the Trust.

2. The Series A Preferred Stock automatically converts into the number of shares of Common Stock as shown in Column 3 without payment of further consideration at the holder's election or upon closing of the initial public offering of the Issuer's common stock. The shares have no expiration date.

3. The option was granted on March 5, 2020. The shares underlying the option vest in full upon the date on which the Board of Directors of the Issuer determines that the Issuer has dosed the initial patient in its first clinical trial, provided that such event occurs on or before July 1, 2023.

4. The option was granted on March 5, 2020. The shares underlying the option vest over four years, with 25% of the shares vesting on March 5, 2021 and the remaining shares vesting in equal quarterly installments thereafter.

Remarks:

President and Chief Executive Officer Exhibit Index: 24.1 Power of Attorney

	/s/ Jennifer Elliott, Attorney-in-Fact	06/11/2020
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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