Upstream Bio, Inc.

Historical 13F Holders

Symbol
UPB
CUSIP
91678A107
All holders as of
Q2 2026
Type
Equity
Class
COM
Reported Value, Excluding Options
Total Filings

13D/G Filers

Investors who own more than 5% of a class must file a Schedule 13D or 13G. Each filer's latest filing for 91678A107 since 12/18/2024, largest first.

Filer % of Class Filed
FMR LLC 13G/A
14.8% 8/6/2025
Event 6/30/2025
Norges Bank 13G/A 7.7% 8/12/2026
Event 6/30/2026
BlackRock, Inc. 13G 5.2% 7/30/2026
Event 6/30/2026
Decheng Capital Global Life Sciences Fund IV, L.P. 13G/A
5.0% 5/15/2026
Event 3/31/2026
Under 5%, checked the "5 percent or less" box, or amended by a later filing (2)
HBM Healthcare Investments (Cayman) Ltd. 13G/A 4.1% 11/14/2025
Event 9/30/2025
TCG Crossover GP I, LLC 13G/A
3.9% 11/14/2025
Event 9/30/2025

13F Holders by Quarter

Period Filings Shares, Excl. Options Value, Excl. Options
2026 Q3 9 648 k $3.42 M
2026 Q2 153 50.8 M $389 M
2026 Q1 148 44.9 M $404 M
2025 Q4 139 51.2 M $1.39 B
2025 Q3 104 44.5 M $837 M
2025 Q2 85 48.4 M $531 M
2025 Q1 80 46.3 M $267 M
2024 Q4 71 42.1 M $690 M