California State Teachers Retirement System (CalSTRS)
UPB

California State Teachers Retirement System (CalSTRS)’s Upstream Bio Inc UPB Stock Holding History

California State Teachers Retirement System (CalSTRS)’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 		$357K Buy
39,661
+25,009
+171% +$450K ﹤0.01% 2136
2025
Q4 		$398K Buy
14,652
+12,476
+573% +$311K ﹤0.01% 2167
2025
Q3 		$40.9K Buy
2,176
+2
+0.1% +$31 ﹤0.01% 2320
2025
Q2 		$23.9K Buy
2,174
+884
+69% +$8.16K ﹤0.01% 2453
2025
Q1 		$7.89K Hold
1,290
– – ﹤0.01% 2837
2024
Q4 		$21.2K Buy
+1,290
New +$28.8K ﹤0.01% 2585

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

California State Teachers Retirement System (CalSTRS)'s UPB Position: Q1 2026 in Review

California State Teachers Retirement System (CalSTRS) increased its Upstream Bio Inc (UPB) stake by 171% in Q1 2026, buying an estimated $450K and bringing the position to 39,661 shares worth $357K. The position accounts for ﹤0.01% of the portfolio, ranked #2136.

California State Teachers Retirement System (CalSTRS) first reported a position in UPB in Q4 2024 and has held it in 6 quarters since. The position peaked at $398K in Q4 2025. 140 funds tracked by Wall St. Rank hold UPB as of Q1 2026.

  • California State Teachers Retirement System (CalSTRS) held 39,661 shares of Upstream Bio Inc worth $357K as of Q1 2026.
  • California State Teachers Retirement System (CalSTRS) bought 25,009 Upstream Bio Inc shares in Q1 2026, an estimated $450K.
  • Upstream Bio Inc made up ﹤0.01% of California State Teachers Retirement System (CalSTRS)'s portfolio in Q1 2026, its #2136 holding.
  • California State Teachers Retirement System (CalSTRS) first reported a position in Upstream Bio Inc in Q4 2024 and has held it in 6 quarters since.
  • California State Teachers Retirement System (CalSTRS)'s Upstream Bio Inc position peaked at $398K in Q4 2025.
  • 140 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q1 2026.

Based on California State Teachers Retirement System (CalSTRS)'s 13F filing for Q1 2026, filed 18 May 2026.