Jane Street
UPB

Jane Street’s Upstream Bio Inc UPB Stock Holding History

Jane Street’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 		$108K Buy
+15,594
New +$131K ﹤0.01% 10547
2025
Q1 		– Sell
-45,549
Closed -$749K – 10966
2024
Q4 		$749K Buy
+45,549
New +$1.02M ﹤0.01% 5941

Other funds holding UPB

Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
O
OrbiMed New York $5.4B AUM 163.13% 1-Year Est. Return
Norges Bank
Norges Bank Oslo, Norway $1T AUM
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
DC
Decheng Capital Menlo Park, California $732M AUM 275.56% 1-Year Est. Return
ES
Enavate Sciences Menlo Park, California $345M AUM 134.64% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Millennium Management
Millennium Management New York $276B AUM 44.8% 1-Year Est. Return
D.E. Shaw & Co
D.E. Shaw & Co New York $210B AUM 57.28% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return

Jane Street's UPB Position: Q2 2026 in Review

Jane Street opened a new position in Upstream Bio Inc (UPB) in Q2 2026: 15,594 shares worth $108K. The stake represents ﹤0.01% of the portfolio and ranks #10547 among its holdings. This is a return to the name: Jane Street previously reported a position in UPB as recently as Q4 2024.

Jane Street first reported a position in UPB in Q4 2024 and has held it in 2 quarters since. The position peaked at $749K in Q4 2024. 150 funds tracked by Wall St. Rank hold UPB as of Q2 2026.

  • Jane Street held 15,594 shares of Upstream Bio Inc worth $108K as of Q2 2026.
  • Upstream Bio Inc was a new Jane Street position in Q2 2026.
  • Upstream Bio Inc made up ﹤0.01% of Jane Street's portfolio in Q2 2026, its #10547 holding.
  • Jane Street first reported a position in Upstream Bio Inc in Q4 2024 and has held it in 2 quarters since.
  • Jane Street's Upstream Bio Inc position peaked at $749K in Q4 2024.
  • 150 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q2 2026.

Based on Jane Street's 13F filing for Q2 2026, filed 14 Aug 2026.