OFM
UPB

Omega Fund Management’s Upstream Bio Inc UPB Stock Holding History

Omega Fund 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
Q1 		– Sell
-1,326,293
Closed -$36M – 11
2025
Q4 		$36M Sell
1,326,293
-30,000
-2% -$747K 12.57% 6
2025
Q3 		$25.5M Sell
1,356,293
-680,000
-33% -$10.6M 11.47% 6
2025
Q2 		$22.4M Hold
2,036,293
– – 14.48% 3
2025
Q1 		$12.5M Hold
2,036,293
– – 7.35% 6
2024
Q4 		$33.5M Buy
+2,036,293
New +$45.5M 21.71% 3

Other funds holding UPB

Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
O
OrbiMed New York $5.05B AUM 125.28% 1-Year Est. Return
BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
DC
Decheng Capital Menlo Park, California $661M AUM 299.97% 1-Year Est. Return
ES
Enavate Sciences Menlo Park, California $352M AUM 220.14% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
YIH
Y-Intercept (HK) Hong Kong $5.05B AUM 17.89% 1-Year Est. Return
Federated Hermes
Federated Hermes Pittsburgh, Pennsylvania $61.5B AUM 30.7% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
Millennium Management
Millennium Management New York $240B AUM 35.51% 1-Year Est. Return

Omega Fund Management's UPB Position: Q1 2026 in Review

Omega Fund Management sold out of Upstream Bio Inc (UPB) in Q1 2026, closing a stake of 1,326,293 shares — an estimated $36M sold.

Omega Fund Management first reported a position in UPB in Q4 2024 and held it in 5 quarters. The position peaked at $36M in Q4 2025. 140 funds tracked by Wall St. Rank hold UPB as of Q1 2026.

  • Omega Fund Management reported no remaining Upstream Bio Inc position as of Q1 2026 after selling out during the quarter.
  • Omega Fund Management sold 1,326,293 Upstream Bio Inc shares in Q1 2026, an estimated $36M.
  • Omega Fund Management first reported a position in Upstream Bio Inc in Q4 2024 and held it in 5 quarters.
  • Omega Fund Management's Upstream Bio Inc position peaked at $36M in Q4 2025.
  • 140 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q1 2026.

Based on Omega Fund Management's 13F filing for Q1 2026, filed 15 May 2026.