GENERATION BIO CO

Historical 13F Holders

Symbol: GBIO
CUSIP: 37148K209
All holders as of: Q4 2025
Type: Equity
Class: COM NEW

Reported Value, Excluding Options

Total Shares Held, Excluding Options

Total Filers

13D/G Filers

Each filer's latest filing for 37148K209 since 12/18/2024, largest first.

Filer	% of Class	Shares	Form	Filed
SymBiosis Capital Partners, LLC 13G/A	6.3%	421,926	13G/A	11/14/2025 Event 9/30/2025
Under 5%, checked the "5 percent or less" box, or amended by a later filing (3)
Renaissance Technologies LLC 13G/A	4.3%	287,614	13G/A	2/12/2026 Event 12/31/2025
Renaissance Technologies LLC	4.3%	287,614
Renaissance Technologies Holdings Corporation	4.3%	287,614
Price T Rowe Associates Inc /MD/ 13G/A	3.1%	209,641	13G/A	2/17/2026 Event 12/31/2025
Baselake Partners, LP 13G/A	0%	0	13G/A	2/11/2026 Event 2/9/2026
Baselake Partners, LP	0%	0
Baselake Management, LLC	0%	0
David Paolella	0%	0

13F Holders by Quarter

Period	Filers	Shares, Excl. Options	Value, Excl. Options	Options Value
2025 Q4	46	4.34 M	$24.6M	$0
2025 Q3	36	3.11 M	$19.0M	$0
2025 Q2	4	117 k	$37.5k	$0