AllianceBernstein
UPB

AllianceBernstein’s Upstream Bio Inc UPB Stock Holding History

AllianceBernstein’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 		$842K Hold
31,010
– – ﹤0.01% 2410
2025
Q4 		$842K Buy
31,010
+11,160
+56% +$278K ﹤0.01% 2422
2025
Q3 		$373K Sell
19,850
-4,710
-19% -$73.2K ﹤0.01% 2840
2025
Q2 		$270K Sell
24,560
-1,066,626
-98% -$9.85M ﹤0.01% 2966
2025
Q1 		$6.68M Sell
1,091,186
-20,151
-2% -$192K ﹤0.01% 1340
2024
Q4 		$18.3M Buy
+1,111,337
New +$24.8M 0.01% 927

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

AllianceBernstein's UPB Position: Q1 2026 in Review

AllianceBernstein held its Upstream Bio Inc (UPB) position steady in Q1 2026 at 31,010 shares worth $842K. The position accounts for ﹤0.01% of the portfolio, ranked #2410.

AllianceBernstein first reported a position in UPB in Q4 2024 and has held it in 6 quarters since. The position peaked at $18.3M in Q4 2024. 140 funds tracked by Wall St. Rank hold UPB as of Q1 2026.

  • AllianceBernstein held 31,010 shares of Upstream Bio Inc worth $842K as of Q1 2026.
  • AllianceBernstein left its Upstream Bio Inc share count unchanged in Q1 2026.
  • Upstream Bio Inc made up ﹤0.01% of AllianceBernstein's portfolio in Q1 2026, its #2410 holding.
  • AllianceBernstein first reported a position in Upstream Bio Inc in Q4 2024 and has held it in 6 quarters since.
  • AllianceBernstein's Upstream Bio Inc position peaked at $18.3M in Q4 2024.
  • 140 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q1 2026.

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