Citadel Advisors
UPB

Citadel Advisors’s Upstream Bio Inc UPB Stock Holding History

Citadel Advisors’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 		$483K Buy
53,700
+43,700
+437% +$786K ﹤0.01% 9396
2025
Q4 		$272K Sell
10,000
-8,900
-47% -$222K ﹤0.01% 10367
2025
Q3 		$356K Buy
+18,900
New +$294K ﹤0.01% 9953

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

Citadel Advisors's UPB Position: Q1 2026 in Review

Citadel Advisors sold out of Upstream Bio Inc (UPB) in Q1 2026, closing a stake of 13,420 shares — an estimated $241K sold.

Citadel Advisors first reported a position in UPB in Q4 2024 and held it in 2 quarters. The position peaked at $2.96M in Q4 2024. 140 funds tracked by Wall St. Rank hold UPB as of Q1 2026.

  • Citadel Advisors reported no remaining Upstream Bio Inc position as of Q1 2026 after selling out during the quarter.
  • Citadel Advisors sold 13,420 Upstream Bio Inc shares in Q1 2026, an estimated $241K.
  • Citadel Advisors first reported a position in Upstream Bio Inc in Q4 2024 and held it in 2 quarters.
  • Citadel Advisors's Upstream Bio Inc position peaked at $2.96M in Q4 2024.
  • 140 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q1 2026.

Based on Citadel Advisors's 13F filing for Q1 2026, filed 15 May 2026.