Prosight Management’s Upstream Bio Inc UPB Stock Holding History

Prosight Management’s Portfolio UPB Stock Details UPB Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	–	Sell	-241,123	Closed	-$2.17M	–	50
2026 Q1	$2.17M	Buy	+241,123	New	+$4.34M	0.36%	31

Other funds holding UPB

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

OrbiMed New York $5.4B AUM 163.13% 1-Year Est. Return

Norges Bank Oslo, Norway $1T AUM

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

Decheng Capital Menlo Park, California $732M AUM 275.56% 1-Year Est. Return

Enavate Sciences Menlo Park, California $345M AUM 134.64% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

Millennium Management New York $276B AUM 44.8% 1-Year Est. Return

D.E. Shaw & Co New York $210B AUM 57.28% 1-Year Est. Return

JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return

Prosight Management's UPB Position: Q2 2026 in Review

Prosight Management sold out of Upstream Bio Inc (UPB) in Q2 2026, closing a stake of 241,123 shares — an estimated $2.17M sold.

Prosight Management first reported a position in UPB in Q1 2026 and held it in 1 quarter. The position peaked at $2.17M in Q1 2026. 149 funds tracked by Wall St. Rank hold UPB as of Q2 2026.

Prosight Management reported no remaining Upstream Bio Inc position as of Q2 2026 after selling out during the quarter.
Prosight Management sold 241,123 Upstream Bio Inc shares in Q2 2026, an estimated $2.17M.
Prosight Management first reported a position in Upstream Bio Inc in Q1 2026 and held it in 1 quarter.
Prosight Management's Upstream Bio Inc position peaked at $2.17M in Q1 2026.
149 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q2 2026.

Based on Prosight Management's 13F filing for Q2 2026, filed 14 Aug 2026.