Upstream Bio, Inc. (UPB)
Healthcare
Biotechnology
—
6.30 $
-4.0%
vs. previous close
Closing price · As of: 31. Jul 2026
Who owns Upstream Bio, Inc. (UPB)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 64.4% of the shares are freely tradable; institutional investors hold 89.5%.
Ownership Structure
Institutional ownership
Share of the stock held by institutional investors (funds, banks, insurers) according to regulatory filings.
89.5%
Insiders
Share of the stock held by the executives, founders and major shareholders of the company itself.
14.9%
Float
Share of stock freely tradable on the market — not locked up in the hands of founders, insiders, or major shareholders.
64.4%
Short % of float
Shares sold short as a percentage of the freely tradable float — high values signal many bets on falling prices.
11.0%
Shares Outstanding
Total number of shares issued. Price times share count gives market cap.
54Mio.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| FMR Inc | 14.89 | 8,101,563 | +7.8 | 03/31/2026 |
| Orbimed Advisors, LLC | 10.46 | 5,693,589 | +0.0 | 03/31/2026 |
| BlackRock Inc | 6.19 | 3,370,689 | +0.8 | 03/31/2026 |
| NORGES BANK | 5.30 | 2,882,647 | +197.2 | 12/31/2025 |
| Decheng Capital LLC | 5.01 | 2,724,868 | -13.3 | 03/31/2026 |
| Enavate Sciences GP, LLC | 4.52 | 2,459,703 | +0.0 | 03/31/2026 |
| Vanguard Group Inc | 4.39 | 2,388,439 | -2.2 | 12/31/2025 |
| Vanguard Capital Management, LLC | 3.44 | 1,873,574 | +0.0 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Vanguard Total Stock Mkt Idx Inv | 2.65 | 1,443,025 | +0.0 | 04/30/2026 |
| Fidelity Small Cap Growth | 2.52 | 1,371,372 | +0.0 | 03/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Data as of: July 31, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.