Generation Bio (GBIO) Form 3 Generation Bio / Tracy Zimmermann ownership change

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^*

Zimmermann Tracy

(Last) (First) (Middle)

C/O GENERATION BIO CO.,

301 BINNEY STREET

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
11/09/2020

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

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

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
Chief Development Officer

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)

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)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (right to buy)	(1)	12/05/2028	Common Stock	101,907	4.6	D
Stock Option (right to buy)	(2)	03/04/2030	Common Stock	12,029	5.16	D

Explanation of Responses:

1. The option to purchase 101,907 shares was granted on December 6, 2018. The shares underlying the option vest over four years, with 25% of the shares vested on October 1, 2019 and the remaining shares vesting in equal quarterly installments thereafter.

2. The option to purchase 12,029 shares was granted on March 5, 2020. The shares underlying the option vest over four years, with 25% of the shares vested on March 5, 2021 and the remaining shares vesting in equal quarterly installments thereafter.

Remarks:

Exhibit Index: 24.1 Power of Attorney

	/s/ Jennifer Elliott, Attorney-in-Fact	11/10/2020
	** 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).
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