Generation Bio Co.

Historical 13F Holders

Symbol
GBIO
CUSIP
37148K100
All holders as of
Q2 2026
Type
Equity
Class
COM
Reported Value, Excluding Options
Total Shares Held, Excluding Options
Total Filers

13D/G Filers

Each filer's latest filing for 37148K100 since 12/18/2024, largest first.

Filer % of Class Filed
Under 5%, checked the "5 percent or less" box, or amended by a later filing (3)
FMR LLC 13G/A
3.5% 8/6/2025
Event 6/30/2025
BlackRock, Inc. 13G/A 1.7% 7/17/2025
Event 6/30/2025
Atlas Venture Fund X, L.P. 13G/A
0% 5/14/2026
Event 3/31/2026

13F Holders by Quarter

Period Filers Shares, Excl. Options Value, Excl. Options
2026 Q2 1 1.00 $0
2026 Q1 2 62.0 $53.3k
2025 Q4 2 27.0 $17.0k
2025 Q3 6 858 k $5.19M
2025 Q2 60 41.3 M $13.3M
2025 Q1 82 47.7 M $19.3M
2024 Q4 81 53.9 M $57.1M
2024 Q3 78 55.2 M $136M
2024 Q2 80 55.5 M $156M
2024 Q1 78 55.0 M $224M
2023 Q4 77 52.6 M $86.7M
2023 Q3 78 57.2 M $217M
2023 Q2 82 57.3 M $315M
2023 Q1 87 57.4 M $247M
2022 Q4 100 57.1 M $225M
2022 Q3 117 57.7 M $306M
2022 Q2 96 55.4 M $364M
2022 Q1 90 56.5 M $416M
2021 Q4 91 55.0 M $390M
2021 Q3 84 48.0 M $1.20B
2021 Q2 99 46.5 M $1.25B
2021 Q1 89 44.6 M $1.27B
2020 Q4 69 32.0 M $906M
2020 Q3 54 29.4 M $896M
2020 Q2 49 28.4 M $581M