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, Q4 2025
Institutional positions in Upstream Bio, Inc. as of Dec 31, 2025. 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
- 133
- +38 vs. Q3 2025
- Shares held
- 51.2M
- +6.71M (+15.1%) vs. Q3 2025
- Total value
- $1.39B
- +$553.1M (+66.1%) vs. Q3 2025
- New holders
- 46
- 42 more added
- Sold out
- 8
- 33 more reduced
Compare with Q3 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, Q4 2025
Shares, value and share of portfolio for each institution holding Upstream Bio, Inc.; share changes are against Q3 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Charles Schwab Investment Management Inc | 284,931 | $7.74M | 0.00% | +1030.0% | Added |
| Jennison Associates LLC | 288,847 | $7.84M | 0.00% | +288,847 | New |
| Alyeska Investment Group, L.P. | 298,329 | $8.10M | 0.02% | +298,329 | New |
| Great Point Partners LLC | 300,000 | $8.14M | 2.64% | 00.0% | Unchanged |
| Goldman Sachs Group Inc | 333,481 | $9.05M | 0.00% | +110,267+49.4% | Added |
| Marshall Wace, LLP | 343,791 | $9.33M | 0.01% | −524,208−60.4% | Reduced |
| Nantahala Capital Management, LLC | 494,971 | $13.4M | 0.80% | −100,000−16.8% | Reduced |
| Millennium Management LLC | 517,264 | $14.0M | 0.01% | +477,151+1,189.5% | Added |
| Barclays PLC | 524,499 | $14.2M | 0.01% | +439,184+514.8% | Added |
| Siren, L.L.C. | 588,450 | $16.0M | 0.48% | −200,000−25.4% | Reduced |
| Vestal Point Capital, LP | 720,000 | $19.5M | 0.72% | +720,000 | New |
| Samsara BioCapital, LLC | 736,047 | $20.0M | 2.06% | −226,107−23.5% | Reduced |
| TCG Crossover Management, LLC | 743,886 | $20.2M | 0.67% | −1,373,217−64.9% | Reduced |
| Integral Health Asset Management, LLC | 750,000 | $20.4M | 1.03% | +175,000+30.4% | Added |
| Woodline Partners LP | 760,252 | $20.6M | 0.08% | +158,000+26.2% | Added |
| Pictet Asset Management Holding SA | 773,148 | $21.0M | 0.02% | +773,148 | New |
| Parkman Healthcare Partners LLC | 834,559 | $22.7M | 2.16% | −8,943−1.1% | Reduced |
| Geode Capital Management, LLC | 851,908 | $23.1M | 0.00% | +34,799+4.3% | Added |
| Wellington Management Group LLP | 894,733 | $24.3M | 0.00% | −230,662−20.5% | Reduced |
| VR Adviser, LLC | 1,169,298 | $31.7M | 1.57% | 00.0% | Unchanged |
| State Street Corp | 1,319,226 | $35.8M | 0.00% | +204,645+18.4% | Added |
| Omega Fund Management, LLC | 1,326,293 | $36.0M | 12.57% | −30,000−2.2% | Reduced |
| Bain Capital Life Sciences Investors, LLC | 1,329,544 | $36.1M | 2.76% | −1,109,994−45.5% | Reduced |
| Altshuler Shaham Ltd | 1,341,540 | $36.4M | 0.56% | −75,282−5.3% | Reduced |
| Janus Henderson Group PLC | 1,527,958 | $41.4M | 0.02% | +1,527,958 | New |
| UBS Group AG | 1,806,243 | $49.0M | 0.01% | +1,533,972+563.4% | Added |
| Vanguard Group Inc | 2,388,439 | $64.8M | 0.00% | −54,112−2.2% | Reduced |
| Enavate Sciences GP, LLC | 2,459,703 | $66.8M | 13.18% | 00.0% | Unchanged |
| Norges Bank | 2,882,647 | $78.3M | 0.01% | +2,882,647 | New |
| Decheng Capital LLC | 3,143,078 | $85.3M | 11.48% | −142,215−4.3% | Reduced |
| BlackRock, Inc. | 3,344,504 | $90.8M | 0.00% | +740,798+28.5% | Added |
| OrbiMed Advisors LLC | 5,693,589 | $154.6M | 3.16% | 00.0% | Unchanged |
| FMR LLC | 7,518,202 | $204.1M | 0.01% | −568,211−7.0% | Reduced |
| Ikarian Capital, LLC | 0 | $0 | 0.00% | −161,113−100.0% | Sold out |
| Balyasny Asset Management LLC | 0 | $0 | 0.00% | −73,131−100.0% | Sold out |
| Boothbay Fund Management, LLC | 0 | $0 | 0.00% | −61,299−100.0% | Sold out |
| Nomura Holdings Inc | 0 | $0 | 0.00% | −28,290−100.0% | Sold out |
| Caption Management, LLC | 0 | $0 | 0.00% | −18,196−100.0% | Sold out |
| Commonwealth Equity Services, LLC | 0 | $0 | 0.00% | −15,503−100.0% | Sold out |
| Group One Trading, L.P. | 0 | $0 | 0.00% | −1,305−100.0% | Sold out |
| Clearstead Advisors, LLC | 0 | $0 | 0.00% | −163−100.0% | Sold out |