EcoR1 Capital’s Generation Bio GBIO Stock Holding History

EcoR1 Capital’s Portfolio GBIO Stock Details GBIO Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2025 Q1	–	Sell	-204,687	Closed	-$2.17M	–	53
2024 Q4	$2.17M	Hold	204,687	–	–	0.08%	51
2024 Q3	$5.06M	Hold	204,687	–	–	0.17%	46
2024 Q2	$5.77M	Hold	204,687	–	–	0.18%	46
2024 Q1	$8.33M	Hold	204,687	–	–	0.21%	47
2023 Q4	$3.38M	Hold	204,687	–	–	0.09%	42
2023 Q3	$7.76M	Hold	204,687	–	–	0.26%	35
2023 Q2	$11.3M	Buy	204,687 +9,029	+5%	+$414K	0.28%	32
2023 Q1	$8.41M	Buy	+195,658	New	+$9.46M	0.27%	33

Other funds holding GBIO

T. Rowe Price Associates Baltimore, Maryland $865B AUM 30.76% 1-Year Est. Return

AVLSA

Atlas Venture Life Science Advisors Cambridge, Massachusetts $790M AUM 223.66% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Siren LLC Greenwich, Connecticut $3.61B AUM 203.3% 1-Year Est. Return

Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return

BBA

Baker Bros. Advisors New York $17.4B AUM 131.5% 1-Year Est. Return

Renaissance Technologies New York $63.9B AUM 45.56% 1-Year Est. Return

Bank of America Charlotte, North Carolina $1.37T AUM 24.88% 1-Year Est. Return

Acadian Asset Management Boston, Massachusetts $70.5B AUM 36% 1-Year Est. Return

EcoR1 Capital's GBIO Position: Q1 2025 in Review

EcoR1 Capital sold out of Generation Bio (GBIO) in Q1 2025, closing a stake of 204,687 shares — an estimated $2.17M sold.

EcoR1 Capital first reported a position in GBIO in Q1 2023 and held it in 8 quarters. The position peaked at $11.3M in Q2 2023. 79 funds tracked by Wall St. Rank hold GBIO as of Q1 2025.

EcoR1 Capital reported no remaining Generation Bio position as of Q1 2025 after selling out during the quarter.
EcoR1 Capital sold 204,687 Generation Bio shares in Q1 2025, an estimated $2.17M.
EcoR1 Capital first reported a position in Generation Bio in Q1 2023 and held it in 8 quarters.
EcoR1 Capital's Generation Bio position peaked at $11.3M in Q2 2023.
79 funds tracked by Wall St. Rank held Generation Bio as of Q1 2025.

Based on EcoR1 Capital's 13F filing for Q1 2025, filed 15 May 2025.