Gossamer Bio, Inc. SEC filings GOSS
Gossamer Bio, Inc. has 484 filings in SEC EDGAR's recent list, going back to Jan 19, 2018. Its latest annual report, Form ARS, was filed on Apr 24, 2026 for the period ended Apr 24, 2026. The latest quarterly report (Form 10-Q) was filed on Aug 13, 2026, covering the quarter ended Jun 30, 2026. The most recent current report (Form 8-K) was filed on Oct 28, 2026 (shareholder vote results). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 29, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Oct 8, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Sep 28, 2026 | — |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 4 | Insider transaction | Sep 25, 2026 | Sep 23, 2026 |
| 3 | Initial insider ownership | Sep 22, 2026 | Sep 16, 2026 |
| 4 | Insider transaction | Aug 26, 2026 | Aug 24, 2026 |
| 4 | Insider transaction | Aug 26, 2026 | Aug 24, 2026 |
| 4 | Insider transaction | Aug 26, 2026 | Aug 24, 2026 |
| 4 | Insider transaction | Aug 26, 2026 | Aug 24, 2026 |
| 4 | Insider transaction | Aug 26, 2026 | Aug 24, 2026 |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Aug 24, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Jul 29, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Jul 29, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Jul 24, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Jul 1, 2026 | — |
| SCHEDULE 13D | Ownership over 5% (active) | Jun 11, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Jun 11, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Jun 11, 2026 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Jun 9, 2026 | — |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| 4 | Insider transaction | Jun 5, 2026 | Jun 4, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | May 14, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Mar 27, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Mar 24, 2026 | — |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| 4 | Insider transaction | Mar 20, 2026 | Mar 19, 2026 |
| SCHEDULE 13G | Ownership over 5% (passive) | Mar 2, 2026 | — |
| SCHEDULE 13D/A | Amended ownership over 5% (active) | Feb 24, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Feb 17, 2026 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Jan 21, 2026 | — |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Jan 5, 2026 | Jan 2, 2026 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Oct 2, 2025 | Oct 1, 2025 |
| 4 | Insider transaction | Aug 20, 2025 | Aug 19, 2025 |
| SCHEDULE 13G | Ownership over 5% (passive) | Jul 29, 2025 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Jul 17, 2025 | — |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Jun 26, 2025 | Jun 25, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| 4 | Insider transaction | Mar 6, 2025 | Mar 4, 2025 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Feb 12, 2025 | — |
| SCHEDULE 13G | Ownership over 5% (passive) | Feb 5, 2025 | — |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Jan 30, 2025 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Nov 12, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Nov 12, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Aug 2, 2024 | — |
| 4 | Insider transaction | Jun 25, 2024 | Jun 24, 2024 |
| 4 | Insider transaction | Jun 24, 2024 | Jun 21, 2024 |
| 4 | Insider transaction | Jun 20, 2024 | Jun 18, 2024 |
| 4 | Insider transaction | Jun 20, 2024 | Jun 17, 2024 |
| 4 | Insider transaction | Jun 6, 2024 | Jun 6, 2024 |
| 4 | Insider transaction | Jun 6, 2024 | Jun 6, 2024 |
| 4 | Insider transaction | Jun 6, 2024 | Jun 6, 2024 |
| 4 | Insider transaction | Jun 6, 2024 | Jun 6, 2024 |
| 4 | Insider transaction | Mar 28, 2024 | Mar 27, 2024 |
| 4 | Insider transaction | Mar 28, 2024 | Mar 27, 2024 |
| 4 | Insider transaction | Mar 28, 2024 | Mar 27, 2024 |
| 4 | Insider transaction | Mar 19, 2024 | Mar 18, 2024 |
| 4 | Insider transaction | Mar 19, 2024 | Mar 18, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 4 | Insider transaction | Mar 12, 2024 | Mar 11, 2024 |
| 3 | Initial insider ownership | Mar 12, 2024 | Mar 11, 2024 |
| 3 | Initial insider ownership | Mar 12, 2024 | Mar 11, 2024 |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 14, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 13, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 9, 2024 | — |
| SC 13G | Ownership over 5% (passive) | Feb 9, 2024 | — |
| SC 13G | Ownership over 5% (passive) | Jan 11, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Jan 11, 2024 | — |
| 4 | Insider transaction | Jan 4, 2024 | Jan 2, 2024 |
| 4 | Insider transaction | Jan 4, 2024 | Jan 2, 2024 |
| 4 | Insider transaction | Jan 4, 2024 | Jan 2, 2024 |
| 4 | Insider transaction | Jan 4, 2024 | Jan 2, 2024 |
| 4 | Insider transaction | Jan 4, 2024 | Jan 2, 2024 |
| 4 | Insider transaction | Dec 5, 2023 | Dec 4, 2023 |
| 3 | Initial insider ownership | Dec 5, 2023 | Dec 4, 2023 |
| 4 | Insider transaction | Nov 29, 2023 | Nov 28, 2023 |
| 3 | Initial insider ownership | Nov 29, 2023 | Nov 28, 2023 |
| 4 | Insider transaction | Nov 22, 2023 | Nov 20, 2023 |
| 4 | Insider transaction | Nov 22, 2023 | Nov 20, 2023 |
| 4 | Insider transaction | Nov 22, 2023 | Nov 20, 2023 |
| 4 | Insider transaction | Nov 22, 2023 | Nov 20, 2023 |
| 4 | Insider transaction | Nov 22, 2023 | Nov 20, 2023 |
| 4 | Insider transaction | Nov 17, 2023 | Nov 15, 2023 |
| 4 | Insider transaction | Nov 14, 2023 | Nov 13, 2023 |
| SC 13D | Ownership over 5% (active) | Jul 28, 2023 | — |
| 4 | Insider transaction | Jul 26, 2023 | Jul 24, 2023 |
| 4 | Insider transaction | Jul 26, 2023 | Jul 24, 2023 |
| 4 | Insider transaction | Jul 26, 2023 | Jul 24, 2023 |
| 4 | Insider transaction | Jun 26, 2023 | Jun 22, 2023 |
| 4 | Insider transaction | Jun 9, 2023 | Jun 8, 2023 |
| 4 | Insider transaction | Jun 9, 2023 | Jun 8, 2023 |
| 4 | Insider transaction | Jun 9, 2023 | Jun 8, 2023 |
| 4 | Insider transaction | Jun 9, 2023 | Jun 8, 2023 |
| 4 | Insider transaction | Jun 9, 2023 | Jun 8, 2023 |
| SC 13G/A | Amended ownership over 5% (passive) | May 10, 2023 | — |
| 4 | Insider transaction | May 9, 2023 | May 5, 2023 |
| 4 | Insider transaction | May 9, 2023 | May 5, 2023 |
| 4 | Insider transaction | May 9, 2023 | May 5, 2023 |
| 4 | Insider transaction | May 9, 2023 | May 5, 2023 |
| 4 | Insider transaction | May 9, 2023 | May 5, 2023 |
| SC 13G/A | Amended ownership over 5% (passive) | May 5, 2023 | — |
| 4 | Insider transaction | Apr 5, 2023 | Apr 4, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 22, 2023 | Mar 20, 2023 |
| 4 | Insider transaction | Mar 20, 2023 | Mar 16, 2023 |
| 4 | Insider transaction | Mar 20, 2023 | Mar 16, 2023 |
| 4 | Insider transaction | Mar 20, 2023 | Mar 16, 2023 |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 14, 2023 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 9, 2023 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 1, 2023 | — |
| SC 13G | Ownership over 5% (passive) | Jan 10, 2023 | — |
| SC 13G | Ownership over 5% (passive) | Jan 4, 2023 | — |
| SC 13G | Ownership over 5% (passive) | Dec 20, 2022 | — |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4 | Insider transaction | Dec 9, 2022 | Dec 7, 2022 |
| 4/A | Form 4/a | Oct 27, 2022 | Oct 24, 2022 |
| 4 | Insider transaction | Oct 25, 2022 | Oct 24, 2022 |
| 4 | Insider transaction | Oct 25, 2022 | Oct 24, 2022 |
| 4 | Insider transaction | Oct 25, 2022 | Oct 24, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jun 9, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jul 15, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jul 15, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jul 15, 2022 |
| 4 | Insider transaction | Jul 15, 2022 | Jul 15, 2022 |
| 4 | Insider transaction | Jul 5, 2022 | Jul 1, 2022 |
| 4 | Insider transaction | Jun 23, 2022 | Jun 22, 2022 |
| 4 | Insider transaction | May 5, 2022 | May 4, 2022 |
| 4 | Insider transaction | Mar 24, 2022 | Mar 23, 2022 |
| 4 | Insider transaction | Mar 24, 2022 | Mar 23, 2022 |
| 4 | Insider transaction | Mar 24, 2022 | Mar 23, 2022 |
| 4 | Insider transaction | Mar 17, 2022 | Mar 16, 2022 |
| 4 | Insider transaction | Mar 17, 2022 | Mar 16, 2022 |
| 4 | Insider transaction | Mar 17, 2022 | Mar 16, 2022 |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 10, 2022 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 3, 2022 | — |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Jan 10, 2022 | Jan 6, 2022 |
| 4 | Insider transaction | Oct 26, 2021 | Oct 25, 2021 |
| 4 | Insider transaction | Oct 26, 2021 | Oct 25, 2021 |
| 4 | Insider transaction | Oct 26, 2021 | Oct 25, 2021 |
| 4 | Insider transaction | Sep 20, 2021 | Sep 16, 2021 |
| 4 | Insider transaction | Jul 1, 2021 | Jun 30, 2021 |
| 4 | Insider transaction | Jun 22, 2021 | Jun 21, 2021 |
| 3 | Initial insider ownership | Jun 22, 2021 | Jun 21, 2021 |
| 4 | Insider transaction | Jun 14, 2021 | Jun 10, 2021 |
| 3 | Initial insider ownership | Jun 14, 2021 | Jun 10, 2021 |
| 4 | Insider transaction | Jun 10, 2021 | Jun 9, 2021 |
| 4 | Insider transaction | Jun 10, 2021 | Jun 9, 2021 |
| 4 | Insider transaction | Jun 10, 2021 | Jun 9, 2021 |
| 4 | Insider transaction | Jun 10, 2021 | Jun 9, 2021 |
| 4 | Insider transaction | Jun 10, 2021 | Jun 9, 2021 |
Showing 200 filings, the most recent 200. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
New to this? Read What Are SEC Filings? 10-K, 10-Q, 8-K and Other Forms Explained.
Company profile
- Industry
- Pharmaceutical Preparations (SIC 2834)
- Listed as
- GOSS (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- San Diego, CA
- SEC filer status
- Non-accelerated filer, Smaller reporting company
- SEC CIK
- 1728117
Other Pharmaceutical Preparations companies
- ELI LILLY & Co LLY
- Johnson & Johnson JNJ
- AbbVie Inc. ABBV
- Merck & Co., Inc. MRK
- Novartis AG NVS
- Astrazeneca PLC AZN
- Abbott Laboratories ABT
- Novo Nordisk A S NVO
Source: SEC EDGAR filings. This is company-reported data, not investment advice.