🕵️ Summit Therapeutics Inc. ($SMMT)
SEC insider & ownership activity, last 12 months · CIK 1599298 · every row links its SEC filing
Over the last 12 months insiders bought $126.6M with no open-market selling against it. Robert W. Duggan bought $57.9M (Sep–Jun). No red-flag 8-Ks in the window.
Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
4 buyers, $126.6M (13 lots) · 0 sellers, $0 (0 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Robert W. Duggan | 5 | $57.9M | 0 | – | Jun 12, 2026 |
| Zanganeh Mahkam | 5 | $57.9M | 0 | – | Jun 12, 2026 |
| Xia Yu | 1 | $10.0M | 0 | – | Oct 21, 2025 |
| Soni Manmeet Singh | 2 | $722K | 0 | – | Jun 4, 2026 |
5%+ holders
No current 5%+ beneficial-ownership positions on file.
Planned insider sales (Form 144)
No sale notices filed in the last 12 months.
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Earnings (2.02) | Jul 23, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Jul 23, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 23, 2026 | filing ↗ |
| Material agreement (1.01) | Jul 23, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 23, 2026 | filing ↗ |
| Other events (8.01) | Jul 22, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 22, 2026 | filing ↗ |
| Shareholder vote (5.07) | Jun 10, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Jun 10, 2026 | filing ↗ |
| Other events (8.01) | Jun 2, 2026 | filing ↗ |
| Other events (8.01) | May 30, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 30, 2026 | filing ↗ |
| Earnings (2.02) | Apr 30, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Apr 30, 2026 | filing ↗ |
| Earnings (2.02) | Feb 23, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Feb 23, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Feb 23, 2026 | filing ↗ |
| Other events (8.01) | Jan 29, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jan 29, 2026 | filing ↗ |
| Earnings (2.02) | Jan 12, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Jan 12, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jan 12, 2026 | filing ↗ |
| Other events (8.01) | Nov 7, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 7, 2025 | filing ↗ |
| Material agreement (1.01) | Oct 21, 2025 | filing ↗ |
| Unregistered equity sale (3.02) | Oct 21, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Oct 21, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Oct 21, 2025 | filing ↗ |
| Earnings (2.02) | Oct 17, 2025 | filing ↗ |
| Other events (8.01) | Oct 17, 2025 | filing ↗ |