| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| FMR LLC | 15% | +11% | $75,400,363 | +$7,226,584 | 7,936,880 | +11% | FMR LLC | 30 Jun 2025 |
| Decheng Capital Global Life Sciences Fund IV, L.P. | 6.1% | $24,212,609 | 3,285,293 | Xiangmin Cui | 31 Dec 2024 | |||
| NORGES BANK | 5.3% | $54,226,626 | 2,882,647 | Norges Bank | 30 Sep 2025 | |||
| HBM Healthcare Investments (Cayman) Ltd. | 4.1% | -20% | $41,293,111 | -$9,780,893 | 2,195,111 | -19% | HBM Healthcare Investments (Cayman) Ltd. | 30 Sep 2025 |
| TCG Crossover GP I, LLC | 3.9% | -26% | $39,825,671 | -$12,879,413 | 2,117,103 | -24% | TCG Crossover GP I, LLC | 30 Sep 2025 |
As of 30 Sep 2025, 94 institutional investors reported holding 44,461,719 shares of Upstream Bio, Inc. - Common Stock, par value $0.001 per share (UPB). This represents 82% of the company’s total 54,284,692 outstanding shares.
The largest institutional shareholders of Upstream Bio, Inc. - Common Stock, par value $0.001 per share (UPB) together control 78% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| FMR LLC | 15% | 8,086,413 | +1.9% | 0.01% | $152,105,434 |
| ORBIMED ADVISORS LLC | 10% | 5,693,589 | 0% | 2.6% | $107,096,409 |
| Decheng Capital LLC | 6.1% | 3,285,293 | 0% | 11% | $61,796,361 |
| BlackRock, Inc. | 4.8% | 2,603,706 | +24% | 0% | $48,975,709 |
| ENAVATE SCIENCES GP, LLC | 4.5% | 2,459,703 | 0% | 14% | $46,267,013 |
| VANGUARD GROUP INC | 4.5% | 2,442,551 | +13% | 0% | $45,944,385 |
| Bain Capital Life Sciences Investors, LLC | 4.5% | 2,439,538 | 0% | 3% | $45,887,710 |
| TCG Crossover Management, LLC | 3.9% | 2,117,103 | -24% | 2% | $39,822,707 |
| Altshuler Shaham Ltd | 2.6% | 1,416,822 | -58% | 0.44% | $26,650,422 |
| Omega Fund Management, LLC | 2.5% | 1,356,293 | -33% | 11% | $25,511,871 |
| VR ADVISER, LLC | 2.2% | 1,169,298 | -49% | 1.2% | $21,994,495 |
| WELLINGTON MANAGEMENT GROUP LLP | 2.1% | 1,125,395 | -8.2% | 0% | $21,168,680 |
| STATE STREET CORP | 2.1% | 1,114,581 | +132% | 0% | $20,965,269 |
| SAMSARA BIOCAPITAL, LLC | 1.8% | 962,154 | -33% | 2.4% | $18,098,117 |
| MARSHALL WACE, LLP | 1.6% | 867,999 | +199% | 0.02% | $16,327,061 |
| Parkman Healthcare Partners LLC | 1.6% | 843,502 | +18% | 1.7% | $15,866,273 |
| GEODE CAPITAL MANAGEMENT, LLC | 1.5% | 817,109 | +26% | 0% | $15,373,245 |
| Siren, L.L.C. | 1.5% | 788,450 | 0% | 0.58% | $14,830,745 |
| Woodline Partners LP | 1.1% | 602,252 | +7.9% | 0.05% | $11,328,360 |
| Nantahala Capital Management, LLC | 1.1% | 594,971 | 0% | 0.69% | $11,191,405 |
| Integral Health Asset Management, LLC | 1.1% | 575,000 | 0.79% | $10,815,750 | |
| GREAT POINT PARTNERS LLC | 0.55% | 300,000 | 0% | 2.4% | $5,643,000 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 0.52% | 284,828 | +60% | 0% | $5,357,615 |
| UBS Group AG | 0.5% | 272,271 | +17% | 0% | $5,121,418 |
| NORTHERN TRUST CORP | 0.47% | 254,719 | +11% | 0% | $4,791,264 |
| Period | Reported Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2025 Q4 | 7,493 | $203,622 | +$160,590 | $27.15 | 5 |
| 2025 Q3 | 44,461,719 | $836,327,467 | -$50,813,161 | $18.81 | 94 |
| 2025 Q2 | 48,353,677 | $530,923,062 | +$32,738,817 | $10.98 | 82 |
| 2025 Q1 | 42,073,968 | $257,482,560 | -$17,702,263 | $6.12 | 76 |
| 2024 Q4 | 42,074,592 | $690,108,943 | +$649,643,077 | $16.44 | 70 |