Generation Bio (GBIO) CFO converts RSUs to stock as merger-triggered vesting completes

Rhea-AI Filing Summary

Generation Bio Co.'s Chief Financial Officer, Kevin John Conway, reported routine equity compensation activity tied to a prior restricted stock unit (RSU) grant. On February 2, 2026, 235 RSUs were exercised into 235 shares of common stock at an exercise price of $0.

In a related transaction the same day, 72 shares of common stock were withheld at a price of $5.64 per share to cover tax obligations, leaving Conway with 2,072 shares of common stock held directly. The RSUs came from a grant of 9,390 units made on January 20, 2023, which fully vested on February 2, 2026 under the terms of the company’s merger agreement with XOMA Royalty Corporation and its subsidiary XRA 7 Corp.

Insider Trade Summary

235 shares exercised/converted

Mixed 3 txns

Insider Conway Kevin John

Role Chief Financial Officer

Type	Security	Shares	Price	Value
Exercise	Restricted Stock Units	235	$0.00	--
Exercise	Common Stock	235	$0.00	--
Tax Withholding	Common Stock	72	$5.64	$406.08

Holdings After Transaction: Restricted Stock Units — 0 shares (Direct); Common Stock — 2,144 shares (Direct)

Footnotes (1)

1. Each restricted stock unit represents the right to receive one share of the company's common stock. 2. The grant of 9,390 restricted stock units was made on January 20, 2023. Pursuant to the terms of that certain Agreement and Plan of Merger, by and among the Issuer, XOMA Royalty Corporation ("Parent") and Parent's wholly-owned subsidiary, XRA 7 Corp., dated as of December 15, 2025 (the "Merger Agreement"), prior to the effective time of the merger as contemplated by the Merger Agreement, each restricted stock unit of the Issuer that was outstanding and unvested became vested in full on February 2, 2026.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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

OMB APPROVAL

OMB Number:			3235-0287
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hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Conway Kevin John

(Last) (First) (Middle)

C/O GENERATION BIO CO.

301 BINNEY ST, SUITE 401

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

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

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

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

3. Date of Earliest Transaction (Month/Day/Year)
02/02/2026

4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/02/2026		M		235	A	(1)	2,144	D
Common Stock	02/02/2026		F		72	D	$5.64	2,072	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	(1)	02/02/2026		M			235	(2)	(2)	Common Stock	235	$0	0	D

Explanation of Responses:

1. Each restricted stock unit represents the right to receive one share of the company's common stock.

2. 2. The grant of 9,390 restricted stock units was made on January 20, 2023. Pursuant to the terms of that certain Agreement and Plan of Merger, by and among the Issuer, XOMA Royalty Corporation ("Parent") and Parent's wholly-owned subsidiary, XRA 7 Corp., dated as of December 15, 2025 (the "Merger Agreement"), prior to the effective time of the merger as contemplated by the Merger Agreement, each restricted stock unit of the Issuer that was outstanding and unvested became vested in full on February 2, 2026.

	/s/ Shawna-Gay White, Attorney-in-Fact	02/04/2026
	** 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 4 (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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FAQ

What insider activity did GBIO’s CFO report on February 2, 2026?

Generation Bio’s CFO, Kevin John Conway, reported exercising 235 restricted stock units into 235 common shares at $0 per share, with 72 shares withheld for taxes. After these transactions, he directly held 2,072 shares of Generation Bio common stock.

How many Generation Bio (GBIO) shares does the CFO own after this Form 4?

After the reported transactions, CFO Kevin John Conway directly owns 2,072 Generation Bio common shares. This reflects the conversion of 235 restricted stock units into stock and the withholding of 72 shares to satisfy tax obligations on February 2, 2026.

What restricted stock unit grant is disclosed in this GBIO Form 4?

The filing notes a grant of 9,390 restricted stock units made on January 20, 2023. These units were subject to vesting and, under the merger agreement with XOMA Royalty Corporation, all outstanding unvested units became fully vested on February 2, 2026.

Why did Generation Bio’s CFO have shares withheld at $5.64?

On February 2, 2026, 72 Generation Bio common shares were withheld at $5.64 per share to cover tax withholding related to the RSU vesting and conversion. This tax settlement reduced the CFO’s post-transaction holdings to 2,072 directly owned shares.

How is the GBIO merger with XOMA Royalty connected to this Form 4?

The filing explains that, under the Agreement and Plan of Merger with XOMA Royalty Corporation and subsidiary XRA 7 Corp., each outstanding unvested Generation Bio restricted stock unit became fully vested on February 2, 2026, triggering the RSU conversion and related tax withholding reported.

What does the RSU conversion in GBIO’s Form 4 mean for shareholders?

The RSU conversion shows routine compensation for the CFO turning 235 restricted stock units into common shares, with part withheld for taxes. It reflects standard equity-based pay practices and the completion of vesting triggered by the company’s merger agreement with XOMA Royalty Corporation.