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 |
|---|---|---|---|---|---|
| Citigroup Inc | 5,055 | $45.5K | 0.00% | −1,894−27.3% | Reduced |
| Vanguard Investments Australia, Ltd. | 4,096 | $36.9K | 0.00% | +4,096 | New |
| CWM, LLC | 3,883 | $34.9K | 0.00% | +523+15.6% | Added |
| Russell Investments Group, Ltd. | 3,647 | $32.8K | 0.00% | +824+29.2% | Added |
| Wellington Grp LLC | 3,000 | $27.0K | 0.01% | +1,000+50.0% | Added |
| Mirae Asset Global Investments Co., Ltd. | 2,819 | $25.4K | 0.00% | +193+7.3% | Added |
| Ameritas Investment Partners, Inc. | 2,741 | $24.7K | 0.00% | 00.0% | Unchanged |
| Tower Research Capital LLC (TRC) | 1,425 | $12.8K | 0.00% | +756+113.0% | Added |
| GF Fund Management Co. Ltd. | 1,203 | $10.8K | 0.00% | +142+13.4% | Added |
| Larson Financial Group LLC | 1,107 | $9.96K | 0.00% | +1,093+7,807.1% | Added |
| Sterling Capital Management LLC | 1,094 | $9.85K | 0.00% | −825−43.0% | Reduced |
| Versant Capital Management, Inc | 762 | $6.86K | 0.00% | +204+36.6% | Added |
| Rockefeller Capital Management L.P. | 738 | $6.64K | 0.00% | +738 | New |
| GAMMA Investing LLC | 715 | $6.43K | 0.00% | −185−20.6% | Reduced |
| Quantbot Technologies LP | 663 | $5.97K | 0.00% | +663 | New |
| US Bancorp | 590 | $5.31K | 0.00% | +44+8.1% | Added |
| UBS Asset Management Americas Inc | 588 | $5.29K | 0.00% | +346+143.0% | Added |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 477 | $4.29K | 0.00% | +477 | New |
| Essential Partners LLC | 402 | $3.62K | 0.00% | +305+314.4% | Added |
| Advisor Group Holdings, Inc. | 389 | $3.50K | 0.00% | +384+7,680.0% | Added |
| Allworth Financial LP | 263 | $2.37K | 0.00% | +195+286.8% | Added |
| EverSource Wealth Advisors, LLC | 222 | $2.00K | 0.00% | −60−21.3% | Reduced |
| MAI Capital Management | 171 | $1.54K | 0.00% | +171 | New |
| Torren Management, LLC | 162 | $1.46K | 0.00% | −937−85.3% | Reduced |
| N.E.W. Advisory Services LLC | 120 | $1.08K | 0.00% | +60+100.0% | Added |
| Natixis | 120 | $1.08K | 0.00% | +120 | New |
| New York State Common Retirement Fund | 100 | $900 | 0.00% | −11,600−99.1% | Reduced |
| Wealth Preservation Advisors, LLC | 86 | $774 | 0.00% | +86 | New |
| Farther Finance Advisors, LLC | 81 | $754 | 0.00% | +81 | New |
| SRS Capital Advisors, Inc. | 77 | $693 | 0.00% | +75+3,750.0% | Added |
| Signaturefd, LLC | 66 | $594 | 0.00% | −51−43.6% | Reduced |
| Rothschild Investment LLC | 61 | $549 | 0.00% | +60+6,000.0% | Added |
| Ameritas Advisory Services, LLC | 31 | $279 | 0.00% | +31 | New |
| Caitong International Asset Management Co., Ltd | 23 | $207 | 0.00% | +23 | New |
| Root Financial Partners, LLC | 20 | $180 | 0.00% | +20 | New |
| Parallel Advisors, LLC | 2 | $18 | 0.00% | 00.0% | Unchanged |
| SJS Investment Consulting Inc. | 2 | $18 | 0.00% | +2 | New |
| IFP Advisors, Inc | 1 | $9 | 0.00% | 00.0% | Unchanged |
| Freestone Grove Partners LP | 1 | $9 | 0.00% | +1 | New |
| Covestor Ltd | 4 | $0 | 0.00% | +4 | New |
| Janus Henderson Group PLC | 0 | $0 | 0.00% | −1,527,958−100.0% | Sold out |
| Omega Fund Management, LLC | 0 | $0 | 0.00% | −1,326,293−100.0% | Sold out |
| VR Adviser, LLC | 0 | $0 | 0.00% | −1,169,298−100.0% | Sold out |
| Integral Health Asset Management, LLC | 0 | $0 | 0.00% | −750,000−100.0% | Sold out |
| Vestal Point Capital, LP | 0 | $0 | 0.00% | −720,000−100.0% | Sold out |
| Siren, L.L.C. | 0 | $0 | 0.00% | −588,450−100.0% | Sold out |
| Great Point Partners LLC | 0 | $0 | 0.00% | −300,000−100.0% | Sold out |
| Jennison Associates LLC | 0 | $0 | 0.00% | −288,847−100.0% | Sold out |
| Squadron Capital Management LLC | 0 | $0 | 0.00% | −230,650−100.0% | Sold out |
| SummitTX Capital, L.P. | 0 | $0 | 0.00% | −116,724−100.0% | Sold out |
| Artia Global Partners LP | 0 | $0 | 0.00% | −68,653−100.0% | Sold out |
| Exome Asset Management LLC | 0 | $0 | 0.00% | −64,845−100.0% | Sold out |
| Ameriprise Financial Inc | 0 | $0 | 0.00% | −56,557−100.0% | Sold out |
| Seven Grand Managers, LLC | 0 | $0 | 0.00% | −50,000−100.0% | Sold out |
| Rafferty Asset Management, LLC | 0 | $0 | 0.00% | −38,683−100.0% | Sold out |
| PSP Research LLC | 0 | $0 | 0.00% | −17,634−100.0% | Sold out |
| Prelude Capital Management, LLC | 0 | $0 | 0.00% | −16,560−100.0% | Sold out |
| Profund Advisors LLC | 0 | $0 | 0.00% | −14,582−100.0% | Sold out |
| Graham Capital Management, L.P. | 0 | $0 | 0.00% | −13,712−100.0% | Sold out |
| Citadel Advisors LLC | 0 | $0 | 0.00% | −13,420−100.0% | Sold out |
| Virtu Financial LLC | 0 | $0 | 0.00% | −12,246−100.0% | Sold out |
| Verition Fund Management LLC | 0 | $0 | 0.00% | −12,020−100.0% | Sold out |
| Two Sigma Investments, LP | 0 | $0 | 0.00% | −10,500−100.0% | Sold out |
| Intech Investment Management LLC | 0 | $0 | 0.00% | −10,396−100.0% | Sold out |
| VARCOV Co. | 0 | $0 | 0.00% | −9,619−100.0% | Sold out |
| ProShare Advisors LLC | 0 | $0 | 0.00% | −8,354−100.0% | Sold out |
| SEI Investments Co | 0 | $0 | 0.00% | −8,087−100.0% | Sold out |
| SG Americas Securities, LLC | 0 | $0 | 0.00% | −5,518−100.0% | Sold out |
| Amalgamated Bank | 0 | $0 | 0.00% | −1,031−100.0% | Sold out |
| Royal Bank of Canada | 0 | $0 | 0.00% | −969−100.0% | Sold out |
| Simplex Trading, LLC | 0 | $0 | 0.00% | −466−100.0% | Sold out |
| Aster Capital Management (DIFC) Ltd | 0 | $0 | 0.00% | −271−100.0% | Sold out |
| Daiwa Securities Group Inc. | 0 | $0 | 0.00% | −180−100.0% | Sold out |
| J.Safra Asset Management Corp | 0 | $0 | 0.00% | −128−100.0% | Sold out |
| The PNC Financial Services Group, Inc. | 0 | $0 | 0.00% | −106−100.0% | Sold out |
| SageView Advisory Group, LLC | 0 | $0 | 0.00% | −30−100.0% | Sold out |
| Sunbelt Securities, Inc. | 0 | $0 | 0.00% | −19−100.0% | Sold out |
| Norges Bank | – | – | – | – | Not filed |
| Vanguard Group Inc | – | – | – | – | Not filed |
| Global Retirement Partners, LLC | – | – | – | – | Not filed |