Day One Biopharmaceuticals, Inc. — Insider Transactions
Form 4 filings by directors, officers, and 10%+ shareholders
SEC rules require corporate insiders — including directors, executive officers, and any shareholder owning more than 10% of a company's shares — to report changes in their ownership within two business days of a transaction. These disclosures are filed as Form 4. Open-market purchases (code P) are generally considered the most meaningful signal, as insiders are spending their own money.
| Insider | Title | Type | Shares | Price | Value | Owns After | Date |
|---|---|---|---|---|---|---|---|
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Gift | 7,225 | — | — | 7,225 | Nov 25, 2025 |
| Dubow Adam | Gen Counsel & Secretary | Option Exercise | 2,963 | — | — | 57,821 | Nov 17, 2025 |
| York Charles N II | COO and CFO | Sale | 4,062 | $8.91 | $36,192 | 294,715 | Nov 15, 2025 |
| Merendino Lauren | Chief Commercial Officer | Option Exercise | 3,687 | — | — | 54,535 | Nov 15, 2025 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 11,687 | — | — | 181,372 | Nov 15, 2025 |
| Dubow Adam | Gen Counsel & Secretary | Option Exercise | 2,963 | — | — | 50,099 | Aug 18, 2025 |
| Merendino Lauren | Chief Commercial Officer | Option Exercise | 3,687 | — | — | 45,697 | Aug 18, 2025 |
| York Charles N II | COO and CFO | Sale | 4,106 | $6.77 | $27,798 | 278,000 | Aug 15, 2025 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 3,562 | — | — | 149,299 | Aug 15, 2025 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Gift | 199,202 | — | — | 20,204 | Jul 10, 2025 |
| Merendino Lauren | Chief Commercial Officer | Option Exercise | 3,687 | — | — | 35,401 | May 16, 2025 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 3,687 | — | — | 51,688 | May 15, 2025 |
| York Charles N II | COO, CFO AND SECRETARY | Option Exercise | 6,625 | — | — | 262,888 | May 15, 2025 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 11,687 | — | — | 159,701 | May 15, 2025 |
| York Charles N II | COO, CFO AND SECRETARY | Option Exercise | 6,625 | — | — | 250,383 | Feb 18, 2025 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 3,687 | — | — | 40,561 | Feb 15, 2025 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Sale | 12,048 | $11.96 | $144,094 | 128,015 | Feb 15, 2025 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 30,000 | $13.31 | $399,300 | 1,034,015 | Dec 10, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Option Exercise | 6,062 | — | — | 1,066,221 | Nov 18, 2024 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 3,687 | — | — | 35,327 | Nov 18, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 3,562 | — | — | 102,494 | Nov 15, 2024 |
| York Charles N II | COO, CFO AND SECRETARY | Option Exercise | 1,375 | — | — | 233,860 | Nov 15, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 18,255 | $16.17 | $295,183 | 1,067,535 | Nov 11, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 11,245 | $16.03 | $180,257 | 1,085,790 | Nov 7, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 500 | $16.02 | $8,010 | 1,097,035 | Oct 31, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 30,000 | $14.22 | $426,600 | 1,097,535 | Sep 10, 2024 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 1,750 | — | — | 26,443 | Aug 15, 2024 |
| York Charles N II | COO, CFO AND SECRETARY | Sale | 2,633 | $14.00 | $36,862 | 232,485 | Aug 15, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 2,232 | $14.00 | $31,248 | 1,127,535 | Aug 15, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 4,750 | — | — | 97,926 | Aug 15, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 20,000 | $16.01 | $320,200 | 1,121,081 | Jul 16, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Gift | 80,619 | — | — | 734,414 | Jul 2, 2024 |
| Ramasastry Saira | — | Sale | 10,000 | $13.19 | $131,900 | 40,485 | Jun 21, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 30,000 | $12.62 | $378,600 | 1,141,081 | Jun 10, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Sale | 7,873 | $16.08 | $126,598 | 654,728 | May 15, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 2,267 | $16.08 | $36,453 | 1,171,081 | May 15, 2024 |
| York Charles N II | COO, CFO AND SECRETARY | Option Exercise | 2,250 | — | — | 220,918 | May 15, 2024 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 1,750 | — | — | 21,297 | May 15, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 10,000 | $16.37 | $163,700 | 1,164,662 | May 10, 2024 |
| York Charles N II | COO, CFO AND SECRETARY | Sale | 52,183 | $17.89 | $933,554 | 225,571 | May 2, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Sale | 6 | $17.94 | $108 | 651,756 | May 1, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 10,000 | $16.02 | $160,200 | 1,174,662 | Apr 18, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 10,000 | $16.01 | $160,100 | 1,184,662 | Mar 25, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 30,000 | $15.24 | $457,200 | 1,194,662 | Mar 11, 2024 |
| Blackman Samuel C. | HEAD OF R&D | Sale | 20,000 | $16.11 | $322,200 | 1,224,662 | Feb 27, 2024 |
| York Charles N II | COO, CFO AND SECRETARY | Option Exercise | 1,375 | — | — | 271,545 | Feb 16, 2024 |
| Bender Jeremy | CHIEF EXECUTIVE OFFICER | Option Exercise | 4,750 | — | — | 717,741 | Feb 16, 2024 |
| Dubow Adam | GENERAL COUNSEL | Option Exercise | 2,962 | — | — | 14,390 | Feb 15, 2024 |
| Blackman Samuel C. | HEAD OF RESEARCH AND DEVELOPME | Option Exercise | 6,062 | — | — | 1,246,920 | Feb 15, 2024 |
| Blackman Samuel C. | Head of Research and Developme | Option Exercise | 1,437 | — | — | 1,238,943 | Nov 16, 2023 |