19 insiders reported 89 Form 4 transactions for Generation Bio Co. (GBIO) over the past 18 months (most recent 2026-02-09). Recent activity: Stehman-Breen Catherine (Director) Sell 4,752 shares, ATLAS VENTURE ASSOCIATES X, L.P. (Insider) Sell 60 shares, Cooper Ronald Harold Wilfred (Director) Sell 950 shares, Atlas Venture Associates Opportunity I, LLC (Insider) Sell 711,193 shares, Atlas Venture Associates Opportunity I, L.P. (Insider) Sell 711,193 shares. Source: SEC Form 4.
| Date | Insider | Title | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-02-09 | Stehman-Breen Catherine | Director | Sell | 4,752 | $0 |
| 2026-02-09 | ATLAS VENTURE ASSOCIATES X, L.P. | Insider | Sell | 60 | $0 |
| 2026-02-09 | Cooper Ronald Harold Wilfred | Director | Sell | 950 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, LLC | Insider | Sell | 711,193 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, L.P. | Insider | Sell | 711,193 | $0 |
| 2026-02-09 | Atlas Venture Opportunity Fund I, L.P. | Insider | Sell | 711,193 | $0 |
| 2026-02-09 | ATLAS VENTURE ASSOCIATES X, L.P. | Insider | Sell | 711,193 | $0 |
| 2026-02-09 | Conway Kevin John | CHIEF FINANCIAL OFFICER | Sell | 2,072 | $0 |
| 2026-02-09 | Atlas Venture Fund X, L.P. | Insider | Sell | 711,193 | $0 |
| 2026-02-09 | Atlas Venture Opportunity Fund I, L.P. | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | Atlas Venture Associates X, LLC | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, LLC | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | Atlas Venture Fund X, L.P. | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, L.P. | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | ATLAS VENTURE ASSOCIATES X, L.P. | Insider | Sell | 116,693 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, L.P. | Insider | Sell | 60 | $0 |
| 2026-02-09 | Atlas Venture Associates Opportunity I, LLC | Insider | Sell | 60 | $0 |
| 2026-02-09 | Atlas Venture Fund X, L.P. | Insider | Sell | 60 | $0 |
| 2026-02-09 | Atlas Venture Opportunity Fund I, L.P. | Insider | Sell | 60 | $0 |
| 2026-02-09 | MCDONOUGH GEOFF | Director | Sell | 138,492 | $0 |
| 2026-02-09 | Atlas Venture Associates X, LLC | Insider | Sell | 60 | $0 |
| 2026-02-09 | Rhodes Jason P | Director | Sell | 711,193 | $0 |
| 2026-02-09 | Rhodes Jason P | Director | Sell | 116,693 | $0 |
| 2026-02-09 | Rhodes Jason P | Director | Sell | 60 | $0 |
| 2026-02-09 | Atlas Venture Associates X, LLC | Insider | Sell | 711,193 | $0 |
Source: SEC Form 4 filings · as of 2026-02-09