Delisting risk
Gossamer Bio
Develops inhaled seralutinib for pulmonary arterial hypertension and PH-ILD.
$0.1726
After-hours close+0.00 (+2.49%)
At close$0.1684(−1.00%)
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Breakdown13F · Form 4
Institutions 34.17%167.04M sharesInsiders 1.55%7.58M sharesOther 64.28%314.23M shares
Shares outstanding 488.85M · Float 128.76M · 26.3% free float
Institutions13F, as of Mar 31, 2026
199 holders · 167.04M shares · 50 new positions · 126 increased · 48 reduced · 57 closed
| Holder | Shares | % outstanding | Chg q/q | Filed |
|---|---|---|---|---|
| BlackRock, Inc. | 16.83M | 3.44% | −230.2K | May 13, 2026 |
| Kalehua Capital Management LLC | 10.24M | 2.09% | +10.24Mnew | May 15, 2026 |
| AQR Capital Management LLC | 10.13M | 2.07% | +9.01M | May 15, 2026 |
| Vanguard Capital Management LLC | 9.39M | 1.92% | +9.39Mnew | May 15, 2026 |
| Arch Venture Management, LLC | 8.06M | 1.65% | 0 | May 15, 2026 |
| Octagon Capital Advisors LP | 7.75M | 1.59% | −6.17M | May 15, 2026 |
| Samsara Biocapital, LLC | 7.22M | 1.48% | 0 | May 15, 2026 |
| Balyasny Asset Management L.P. | 5.92M | 1.21% | +4.41M | May 15, 2026 |
Beneficial owners13D/G · 5% or more, as filed
| Holder | % of class | Shares | Form | Filed |
|---|---|---|---|---|
| 683 Capital Management, LLC | 9.99% | 49.87M | 13G | Jun 11, 2026 ↗ |
| Context Capital Management, LLC | 9.90% | 48.84M | 13G | Jun 9, 2026 ↗ |
| DeepCurrents Investment Group LLC | 7.70% | 37.67M | 13G | Jun 11, 2026 ↗ |
| BlackRock, Inc. | 6.50% | 15.07M | 13G | Jan 21, 2026 ↗ |
| D. E. Shaw & Co., L.P.incl. D. E. Shaw Valence Portfolios, L.L.C., David E. Shaw +1 more | 6.00% | 29.13M | 13D | Aug 24, 2026 ↗ |
| Opaleye Management Inc. | 5.10% | 24.94M | 13G | Jul 29, 2026 ↗ |
InsidersForm 4
| Insider | Role | Shares | % outstanding | Filed |
|---|---|---|---|---|
| Faheem Hasnain | director, officer: President & CEO | 5.33M | 1.09% | Jan 5, 2026 |
| Waage Christian | officer: EVP, Tech Ops and Admin | 814.1K | 0.17% | Jan 5, 2026 |
| Richard Aranda | officer: Chief Medical Officer | 463.1K | 0.09% | Jan 5, 2026 |
| Bryan Giraudo | officer: COO/CFO | 389.7K | 0.08% | Jan 5, 2026 |
| Robert Paul JR Smith | officer: Chief Commercial Officer | 260.9K | 0.05% | Jan 5, 2026 |
| Caryn Peterson | officer: EVP, Regulatory Affairs | 259.3K | 0.05% | Jan 5, 2026 |
| Sandra Milligan | director | 58.1K | 0.01% | Aug 20, 2025 |
2 ten-percent owners hold 10.24M shares by Form 4, outside the officers-and-directors figure above · 7 people have not refiled in the last 18 months (4.25M shares), so they are not in the figure above
Latest trades
No open-market trades in the last 12 months.
CongressHouse and Senate disclosures
Not reported.