Upstream Bio, Inc.
UPB- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0002022626
In the last 90 days, Upstream Bio, Inc. insiders filed 0 open-market purchases and 5 sales; 148 institutions reported holding it in 13F filings for Q2 2026, worth $350.1M in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Upstream Bio, Inc. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 140
- +10 vs. Q4 2025
- Shares held
- 44.9M
- −1.02M (−2.2%) vs. Q4 2025
- Total value
- $404.5M
- −$841.8M (−67.5%) vs. Q4 2025
- New holders
- 47
- 47 more added
- Sold out
- 37
- 35 more reduced
3 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting UPB on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 148 | $350.1M |
| Q1 2026 | 140 | $404.5M |
| Q4 2025 | 133 | $1.39B |
| Q3 2025 | 95 | $836.3M |
| Q2 2025 | 83 | $530.9M |
| Q1 2025 | 79 | $266.9M |
| Q4 2024 | 70 | $690.1M |
| Q3 2024 | 0 | $0 |
| Q2 2024 | 0 | $0 |
| Q1 2024 | 0 | $0 |
| Q4 2023 | 0 | $0 |
| Q3 2023 | 0 | $0 |
| Q2 2023 | 0 | $0 |
| Q1 2023 | 0 | $0 |
| Q4 2022 | 0 | $0 |
| Q3 2022 | 0 | $0 |
| Q2 2022 | 0 | $0 |
| Q1 2022 | 0 | $0 |
| Q4 2021 | 0 | $0 |
| Q3 2021 | 0 | $0 |
| Q2 2021 | 0 | $0 |
| Q1 2021 | 0 | $0 |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Upstream Bio, Inc.; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| FMR LLC | 8,101,563 | $72.9M | 0.00% | +583,361+7.8% | Added |
| OrbiMed Advisors LLC | 5,693,589 | $51.2M | 1.16% | 00.0% | Unchanged |
| BlackRock, Inc. | 3,370,689 | $30.3M | 0.00% | +26,185+0.8% | Added |
| Decheng Capital LLC | 2,724,868 | $24.5M | 3.71% | −418,210−13.3% | Reduced |
| Enavate Sciences GP, LLC | 2,459,703 | $22.1M | 6.30% | 00.0% | Unchanged |
| Vanguard Capital Management LLC | 1,873,574 | $16.9M | 0.00% | +1,873,574 | New |
| Y-Intercept (Hong Kong) Ltd | 1,000,631 | $9.01M | 0.17% | +954,072+2,049.2% | Added |
| Federated Hermes, Inc. | 979,758 | $8.82M | 0.01% | +979,276+203,169.3% | Added |
| Geode Capital Management, LLC | 950,617 | $8.56M | 0.00% | +98,709+11.6% | Added |
| Millennium Management LLC | 937,323 | $8.44M | 0.01% | +420,059+81.2% | Added |
| SEB Asset Management AB | 878,473 | $7.91M | 0.03% | +878,473 | New |
| Bain Capital Life Sciences Investors, LLC | 867,211 | $7.80M | 0.70% | −462,333−34.8% | Reduced |
| Woodline Partners LP | 831,481 | $7.48M | 0.03% | +71,229+9.4% | Added |
| D. E. Shaw & Co., Inc. | 820,480 | $7.38M | 0.01% | +793,389+2,928.6% | Added |
| Parkman Healthcare Partners LLC | 786,783 | $7.08M | 0.73% | −47,776−5.7% | Reduced |
| Samsara BioCapital, LLC | 736,047 | $6.62M | 0.64% | 00.0% | Unchanged |
| Pictet Asset Management Holding SA | 733,431 | $6.60M | 0.01% | −39,717−5.1% | Reduced |
| Vanguard Portfolio Management LLC | 727,711 | $6.55M | 0.00% | +727,711 | New |
| State Street Corp | 705,350 | $6.35M | 0.00% | −613,876−46.5% | Reduced |
| HSBC Holdings PLC | 640,326 | $5.76M | 0.00% | +640,326 | New |
| Qube Research & Technologies Ltd | 619,321 | $5.57M | 0.01% | +619,321 | New |
| Morgan Stanley | 552,609 | $4.97M | 0.00% | +430,541+352.7% | Added |
| JPMorgan Chase & Co | 463,001 | $4.07M | 0.00% | +352,721+319.8% | Added |
| Nantahala Capital Management, LLC | 400,000 | $3.60M | 0.22% | −94,971−19.2% | Reduced |
| Altshuler Shaham Ltd | 380,061 | $3.42M | 0.06% | −961,479−71.7% | Reduced |
| Sphera Funds Management Ltd. | 358,000 | $3.22M | 0.55% | +358,000 | New |
| Propel Bio Management, LLC | 341,779 | $3.10M | 1.95% | +341,779 | New |
| Wellington Management Group LLP | 342,353 | $3.08M | 0.00% | −552,380−61.7% | Reduced |
| Jump Financial, LLC | 319,400 | $2.87M | 0.04% | +319,400 | New |
| Goldman Sachs Group Inc | 316,587 | $2.85M | 0.00% | −16,894−5.1% | Reduced |
| Alyeska Investment Group, L.P. | 298,329 | $2.68M | 0.01% | 00.0% | Unchanged |
| Northern Trust Corp | 260,992 | $2.35M | 0.00% | +24,193+10.2% | Added |
| Charles Schwab Investment Management Inc | 257,729 | $2.32M | 0.00% | −27,202−9.5% | Reduced |
| Prosight Management, LP | 241,123 | $2.17M | 0.36% | +241,123 | New |
| UBS Group AG | 231,254 | $2.08M | 0.00% | −1,574,989−87.2% | Reduced |
| Vanguard Fiduciary Trust Co | 224,157 | $2.02M | 0.00% | +224,157 | New |
| XTX Topco Ltd | 209,277 | $1.88M | 0.03% | +194,186+1,286.8% | Added |
| Arrowstreet Capital, Limited Partnership | 185,087 | $1.67M | 0.00% | +185,087 | New |
| TCG Crossover Management, LLC | 181,063 | $1.63M | 0.05% | −562,823−75.7% | Reduced |
| Deutsche Bank AG | 180,889 | $1.63M | 0.00% | +53,074+41.5% | Added |
| Point72 Asset Management, L.P. | 178,168 | $1.60M | 0.00% | +178,168 | New |
| Trexquant Investment LP | 176,657 | $1.59M | 0.01% | +145,608+469.0% | Added |
| Schonfeld Strategic Advisors LLC | 161,349 | $1.45M | 0.01% | +45,542+39.3% | Added |
| Boxer Capital Management, LLC | 150,000 | $1.35M | 0.18% | 00.0% | Unchanged |
| BNP Paribas Arbitrage, SA | 126,000 | $1.13M | 0.00% | +121,024+2,432.2% | Added |
| Alliancebernstein L.P. | 31,010 | $841.9K | 0.00% | 00.0% | Unchanged |
| ExodusPoint Capital Management, LP | 91,431 | $822.9K | 0.01% | +16,029+21.3% | Added |
| American Century Companies Inc | 87,624 | $788.6K | 0.00% | −132−0.2% | Reduced |
| Bank of New York Mellon Corp | 81,383 | $732.4K | 0.00% | −3,470−4.1% | Reduced |
| Dimensional Fund Advisors LP | 80,002 | $719.5K | 0.00% | +80,002 | New |
| Simplify Asset Management Inc. | 77,793 | $700.1K | 0.01% | +77,793 | New |
| Nuveen, LLC | 75,536 | $679.8K | 0.00% | −3,032−3.9% | Reduced |
| EntryPoint Capital, LLC | 73,568 | $662.1K | 0.19% | +73,568 | New |
| AQR Capital Management LLC | 72,171 | $649.5K | 0.00% | +41,668+136.6% | Added |
| Marshall Wace, LLP | 66,770 | $600.9K | 0.00% | −277,021−80.6% | Reduced |
| Renaissance Technologies LLC | 62,100 | $558.9K | 0.00% | +45,700+278.7% | Added |
| Quantinno Capital Management LP | 49,389 | $444.5K | 0.00% | +33,974+220.4% | Added |
| Bank of America Corp | 48,460 | $436.1K | 0.00% | −37,924−43.9% | Reduced |
| Swiss National Bank | 48,100 | $432.9K | 0.00% | +21,500+80.8% | Added |
| Squarepoint Ops LLC | 44,626 | $401.6K | 0.00% | +44,626 | New |
| Alps Advisors Inc | 43,992 | $395.9K | 0.00% | −384−0.9% | Reduced |
| State of Wisconsin Investment Board | 41,671 | $375.0K | 0.00% | +41,671 | New |
| Rhumbline Advisers | 41,203 | $370.8K | 0.00% | −320−0.8% | Reduced |
| Invesco Ltd. | 40,510 | $364.6K | 0.00% | −122,676−75.2% | Reduced |
| California State Teachers Retirement System | 39,661 | $356.9K | 0.00% | +25,009+170.7% | Added |
| Gsa Capital Partners LLP | 39,232 | $353.0K | 0.02% | +39,232 | New |
| Stonepine Capital Management, LLC | 35,000 | $315.0K | 0.28% | +35,000 | New |
| ADAR1 Capital Management, LLC | 35,000 | $315.0K | 0.02% | +35,000 | New |
| Aquatic Capital Management LLC | 31,484 | $283.4K | 0.01% | +31,484 | New |
| Bleakley Financial Group, LLC | 28,864 | $259.8K | 0.00% | +28,864 | New |
| Axq Capital, LP | 27,503 | $247.5K | 0.03% | +27,503 | New |
| Mariner, LLC | 27,314 | $245.8K | 0.00% | +15,484+130.9% | Added |
| Price T Rowe Associates Inc | 26,434 | $238.0K | 0.00% | +6,798+34.6% | Added |
| Tudor Investment Corp Et Al | 26,412 | $237.7K | 0.00% | +26,412 | New |
| Martingale Asset Management L P | 26,223 | $236.0K | 0.01% | +26,223 | New |
| Victory Capital Management Inc | 25,866 | $232.8K | 0.00% | +25,866 | New |
| Barclays PLC | 24,720 | $222.5K | 0.00% | −499,779−95.3% | Reduced |
| DnB Asset Management AS | 23,515 | $211.6K | 0.00% | +10,722+83.8% | Added |
| Entropy Technologies, LP | 23,336 | $210.0K | 0.01% | +23,336 | New |
| Diadema Partners LP | 21,609 | $194.5K | 0.08% | +1,109+5.4% | Added |
| Man Group plc | 21,154 | $190.4K | 0.00% | +21,154 | New |
| Nisa Investment Advisors, LLC | 19,558 | $176.0K | 0.00% | +19,158+4,789.5% | Added |
| MetLife Investment Management | 19,380 | $174.4K | 0.00% | −298−1.5% | Reduced |
| Wells Fargo & Company | 18,402 | $165.6K | 0.00% | −18,392−50.0% | Reduced |
| Susquehanna International Group, LLP | 15,961 | $143.6K | 0.00% | −39,880−71.4% | Reduced |
| Mirae Asset Global ETFs Holdings Ltd. | 15,608 | $140.5K | 0.00% | −1,883−10.8% | Reduced |
| Manufacturers Life Insurance Company, The | 15,338 | $138.0K | 0.00% | +5,191+51.2% | Added |
| Franklin Resources Inc | 14,589 | $131.3K | 0.00% | +14,589 | New |
| Vanguard Global Advisers, LLC | 13,059 | $117.5K | 0.00% | +13,059 | New |
| CI Private Wealth, LLC | 12,157 | $109.4K | 0.00% | +12,157 | New |
| Creative Planning | 10,850 | $97.7K | 0.00% | −899−7.7% | Reduced |
| Virtus Investment Advisers, Inc. | 10,046 | $90.4K | 0.02% | +245+2.5% | Added |
| Shay Capital LLC | 10,000 | $90.0K | 0.01% | +10,000 | New |
| STRS Ohio | 9,800 | $88.2K | 0.00% | 00.0% | Unchanged |
| Legal & General Group Plc | 9,609 | $86.5K | 0.00% | −4,100−29.9% | Reduced |
| China Universal Asset Management Co., Ltd. | 9,590 | $86.3K | 0.01% | +784+8.9% | Added |
| Police & Firemen's Retirement System of New Jersey | 9,456 | $85.1K | 0.00% | 00.0% | Unchanged |
| Vanguard Asset Management, Ltd | 9,250 | $83.3K | 0.00% | +9,250 | New |
| KLP Kapitalforvaltning AS | 5,900 | $53.1K | 0.00% | +3,000+103.4% | Added |
| Persistent Asset Partners Ltd | 5,495 | $49.5K | 0.02% | −3,412−38.3% | Reduced |