Gossamer Bio's top three insider shareholders as of September 09, 2026 are Waage Christian (Evp, Tech Ops And Admin, 814.06K shares), Bryan Giraudo (Coo/Cfo, 480.01K shares), Richard Aranda (Chief Medical Officer, 463.11K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Waage Christian | Evp, Tech Ops And Admin | 814,061 | 0 | 814,061 | 36.0% | 05 Jan, 2026 |
| 2 | Richard Aranda | Chief Medical Officer | 463,106 | 0 | 463,106 | 20.5% | 05 Jan, 2026 |
| 3 | Bryan Giraudo | Coo/Cfo | 389,737 | 0 | 389,737 | 17.2% | 05 Jan, 2026 |
| 4 | Robert Paul Jr Smith | Chief Commercial Officer | 260,898 | 0 | 260,898 | 11.5% | 05 Jan, 2026 |
| 5 | Caryn Peterson | Evp, Regulatory Affairs | 259,333 | 0 | 259,333 | 11.5% | 05 Jan, 2026 |
| 6 | Laura Carter | Chief Scientific Officer | 76,263 | 0 | 76,263 | 3.4% | 20 Mar, 2023 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 24 Aug, 2026 | Robert Paul Jr Smith | Chief Commercial Officer | Acquired A | 5,800,051 | $0.00 | $0 | 5,800,051 | Direct |
| 24 Aug, 2026 | Bryan Giraudo | Coo/Cfo | Acquired A | 25 | $1,000.00 | $25.00K | 25 | Indirect |
| 24 Aug, 2026 | Faheem Hasnain | President Ceo | Acquired A | 166 | $1,000.00 | $166.00K | 166 | Indirect |
| 24 Aug, 2026 | Caryn Peterson | Chief Development Officer | Acquired A | 5,800,051 | $0.00 | $0 | 5,800,051 | Direct |
| 24 Aug, 2026 | Bryan Giraudo | Coo/Cfo | Acquired A | 5,800,051 | $0.00 | $0 | 5,800,051 | Direct |
| 24 Aug, 2026 | Faheem Hasnain | President Ceo | Acquired A | 5,800,051 | $0.00 | $0 | 5,800,051 | Direct |
| 24 Aug, 2026 | Waage Christian | Evp, Tech Ops And Admin | Acquired A | 2,900,026 | $0.00 | $0 | 2,900,026 | Direct |
| 04 Jun, 2026 | Steven D Nathan | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 04 Jun, 2026 | John D Quisel | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 04 Jun, 2026 | Skye Drynan | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 04 Jun, 2026 | Thomas O Daniel | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 04 Jun, 2026 | Russell J. Cox | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 04 Jun, 2026 | Sandra Milligan | Director | Acquired A | 115,000 | $0.00 | $0 | 115,000 | Direct |
| 19 Mar, 2026 | Caryn Peterson | Evp, Regulatory Affairs | Disposed D | 506,250 | — | — | 0 | Direct |
| 19 Mar, 2026 | Richard Aranda | Chief Medical Officer | Disposed D | 562,500 | — | — | 0 | Direct |
| 19 Mar, 2026 | Robert Paul Jr Smith | Chief Commercial Officer | Disposed D | 562,500 | — | — | 0 | Direct |
| 19 Mar, 2026 | Caryn Peterson | Evp, Regulatory Affairs | Disposed D | 506,250 | — | — | 0 | Direct |
| 19 Mar, 2026 | Caryn Peterson | Evp, Regulatory Affairs | Disposed D | 506,250 | — | — | 0 | Direct |
| 19 Mar, 2026 | Caryn Peterson | Evp, Regulatory Affairs | Disposed D | 506,250 | — | — | 0 | Direct |
| 19 Mar, 2026 | Bryan Giraudo | Coo/Cfo | Disposed D | 693,750 | — | — | 0 | Direct |