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.
Holders of 5% or more of UPB
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Upstream Bio, Inc., largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| FMR LLC | 13G/A | 14.80%7.94M shares | +1.40 ppfrom 13.40% | Feb 12, 20252 filings | Aug 6, 2025 | SEC |
| Decheng Capital Global Life Sciences Fund IV, L.P. | 13G | 6.10%3.29M shares | New | Feb 14, 20251 filing | Feb 14, 2025 | SEC |
| Norges Bank | 13G | 5.30%2.88M shares | New | Oct 24, 20251 filing | Oct 24, 2025 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
8 Schedule 13D and 13G filings on Upstream Bio, Inc., newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Nov 14, 20254:27 PM ET | TCG Crossover GP I, LLCand 2 others | 13G/A | 3.90%2.12M shares | −1.30 ppfrom 5.20%Below 5% | Sep 30, 2025 | SEC |
| Nov 14, 20254:05 PM ET | HBM Healthcare Investments (Cayman) Ltd. | 13G/A | 4.10%2.20M shares | −1.00 ppfrom 5.10%Below 5% | Sep 30, 2025 | SEC |
| Oct 24, 20254:48 PM ET | Norges Bank | 13G | 5.30%2.88M shares | New | Sep 30, 2025 | SEC |
| Aug 6, 202512:19 PM ET | FMR LLCand 1 other | 13G/A | 14.80%7.94M shares | +1.40 ppfrom 13.40% | Jun 30, 2025 | SEC |
| Feb 14, 20255:38 PM ET | Decheng Capital Global Life Sciences Fund IV, L.P.and 4 others | 13G | 6.10%3.29M shares | New | Dec 31, 2024 | SEC |
| Feb 14, 20254:23 PM ET | TCG Crossover GP I, LLCand 2 others | 13G | 5.20%2.80M shares | New | Dec 31, 2024 | SEC |
| Feb 13, 20254:16 PM ET | HBM Healthcare Investments (Cayman) Ltd. | 13G | 5.10%2.72M shares | New | Dec 31, 2024 | SEC |
| Feb 12, 20259:34 AM ET | FMR LLCand 1 other | 13G/A | 13.40%7.18M shares | – | Dec 31, 2024 | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Upstream Bio, Inc. shares.
No Form 144 notices for Upstream Bio, Inc. are on file.