Marshall Wace
UPB

Marshall Wace’s Upstream Bio Inc UPB Stock Holding History

Marshall Wace’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
-66,770
Closed -$601K – 3855
2026
Q1 		$601K Sell
66,770
-277,021
-81% -$4.98M ﹤0.01% 2363
2025
Q4 		$9.33M Sell
343,791
-524,208
-60% -$13M 0.01% 899
2025
Q3 		$16.3M Buy
867,999
+577,473
+199% +$8.97M 0.02% 742
2025
Q2 		$3.19M Sell
290,526
-14,437
-5% -$133K ﹤0.01% 1346
2025
Q1 		$1.87M Buy
304,963
+14,229
+5% +$136K ﹤0.01% 1495
2024
Q4 		$4.78M Buy
+290,734
New +$6.49M 0.01% 1085

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

Marshall Wace's UPB Position: Q2 2026 in Review

Marshall Wace sold out of Upstream Bio Inc (UPB) in Q2 2026, closing a stake of 66,770 shares — an estimated $601K sold.

Marshall Wace first reported a position in UPB in Q4 2024 and held it in 6 quarters. The position peaked at $16.3M in Q3 2025. 148 funds tracked by Wall St. Rank hold UPB as of Q2 2026.

  • Marshall Wace reported no remaining Upstream Bio Inc position as of Q2 2026 after selling out during the quarter.
  • Marshall Wace sold 66,770 Upstream Bio Inc shares in Q2 2026, an estimated $601K.
  • Marshall Wace first reported a position in Upstream Bio Inc in Q4 2024 and held it in 6 quarters.
  • Marshall Wace's Upstream Bio Inc position peaked at $16.3M in Q3 2025.
  • 148 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q2 2026.

Based on Marshall Wace's 13F filing for Q2 2026, filed 13 Aug 2026.