C4 Therapeutics, 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 |
|---|---|---|---|---|---|---|---|
| Mahaney Paige | Chief Scientific Officer | Tax Withholding | 5,644 | $2.58 | $14,562 | 99,356 | Oct 28, 2025 |
| Anderson Kenneth Carl | — | Award / Grant | 5,349 | $2.15 | $11,500 | 140,574 | Oct 1, 2025 |
| GROGAN DONNA ROY | — | Award / Grant | 6,740 | $2.15 | $14,491 | 58,629 | Oct 1, 2025 |
| Adams Kendra | Chief Financial Officer | Tax Withholding | 2,775 | $3.32 | $9,213 | 162,342 | Sep 18, 2025 |
| REYNO LEONARD | Chief Medical Officer | Option Exercise | 15,325 | — | — | 173,764 | Jul 10, 2025 |
| REYNO LEONARD | Chief Medical Officer | Tax Withholding | 7,382 | $1.99 | $14,690 | 166,382 | Jul 10, 2025 |
| Anderson Kenneth Carl | — | Award / Grant | 7,616 | $1.51 | $11,500 | 135,225 | Jul 1, 2025 |
| GROGAN DONNA ROY | — | Award / Grant | 9,609 | $1.51 | $14,510 | 51,889 | Jul 1, 2025 |
| GROGAN DONNA ROY | — | Award / Grant | 9,581 | $1.44 | $13,797 | 42,280 | Apr 1, 2025 |
| Anderson Kenneth Carl | — | Award / Grant | 7,841 | $1.44 | $11,291 | 127,609 | Apr 1, 2025 |
| Hirsch Andrew | President & CEO | Tax Withholding | 12,847 | $3.18 | $40,853 | 432,515 | Feb 14, 2025 |
| Siegel Jolie | Chief Legal Officer | Tax Withholding | 2,914 | $3.18 | $9,267 | 107,939 | Feb 14, 2025 |
| Boyle Scott N | Chief Business Officer | Tax Withholding | 2,368 | $3.18 | $7,530 | 108,474 | Feb 14, 2025 |
| Mossler Mark | Chief Accounting Officer | Tax Withholding | 1,586 | $3.18 | $5,043 | 18,204 | Feb 14, 2025 |
| Schick Kelly | Chief People Officer | Tax Withholding | 2,368 | $3.18 | $7,530 | 108,885 | Feb 14, 2025 |
| Mahaney Paige | Chief Scientific Officer | Award / Grant | 28,200 | — | — | 105,000 | Feb 14, 2025 |
| REYNO LEONARD | Chief Medical Officer | Award / Grant | 87,100 | — | — | 178,909 | Feb 14, 2025 |
| Adams Kendra | Chief Financial Officer | Award / Grant | 87,100 | — | — | 169,676 | Feb 13, 2025 |
| GROGAN DONNA ROY | — | Award / Grant | 3,757 | $3.66 | $13,751 | 32,699 | Jan 2, 2025 |
| Anderson Kenneth Carl | — | Award / Grant | 3,074 | $3.66 | $11,251 | 119,768 | Jan 2, 2025 |
| Boyle Scott N | Chief Business Officer | Option Exercise | 3,750 | — | — | 57,669 | Nov 7, 2024 |
| Adams Kendra | Chief Financial Officer | Tax Withholding | 1,102 | $6.04 | $6,656 | 84,439 | Nov 7, 2024 |
| Schick Kelly | Chief People Officer | Tax Withholding | 1,102 | $6.04 | $6,656 | 56,488 | Nov 7, 2024 |
| Siegel Jolie | Chief Legal Officer | Option Exercise | 3,750 | — | — | 57,590 | Nov 7, 2024 |
| Hirsch Andrew | President & CEO | Option Exercise | 12,500 | — | — | 227,412 | Nov 7, 2024 |
| Mahaney Paige | Chief Scientific Officer | Award / Grant | 76,800 | — | — | 76,800 | Oct 28, 2024 |
| GROGAN DONNA ROY | — | Award / Grant | 2,474 | $5.56 | $13,755 | 28,942 | Oct 1, 2024 |
| Anderson Kenneth Carl | — | Award / Grant | 2,023 | $5.56 | $11,248 | 116,694 | Oct 1, 2024 |
| Adams Kendra | Chief Financial Officer | Tax Withholding | 1,837 | $6.38 | $11,720 | 81,791 | Sep 18, 2024 |
| Hirsch Andrew | President & CEO | Option Exercise | 7,500 | — | — | 218,241 | Sep 16, 2024 |
| Boyle Scott N | Chief Business Officer | Option Exercise | 2,250 | — | — | 54,580 | Sep 16, 2024 |
| Adams Kendra | Chief Financial Officer | Option Exercise | 2,250 | — | — | 84,289 | Sep 16, 2024 |
| Fisher Stewart | Chief Scientific Officer | Tax Withholding | 661 | $6.36 | $4,204 | 130,710 | Sep 16, 2024 |
| Schick Kelly | Chief People Officer | Tax Withholding | 661 | $6.36 | $4,204 | 53,840 | Sep 16, 2024 |
| Siegel Jolie | Chief Legal Officer | Option Exercise | 2,250 | — | — | 54,501 | Sep 16, 2024 |
| REYNO LEONARD | Chief Medical Officer | Tax Withholding | 6,191 | $5.00 | $30,955 | 91,809 | Jul 10, 2024 |
| GROGAN DONNA ROY | — | Award / Grant | 2,836 | $4.85 | $13,755 | 26,468 | Jul 1, 2024 |
| Anderson Kenneth Carl | — | Award / Grant | 2,320 | $4.85 | $11,252 | 114,671 | Jul 1, 2024 |
| Anderson Kenneth Carl | — | Award / Grant | 1,389 | $8.10 | $11,251 | 112,351 | Apr 1, 2024 |
| Dubin Glenn | — | Award / Grant | 1,358 | $8.10 | $11,000 | 22,075 | Apr 1, 2024 |
| GROGAN DONNA ROY | — | Award / Grant | 1,697 | $8.10 | $13,746 | 23,632 | Apr 1, 2024 |
| Hirsch Andrew | President & CEO | Tax Withholding | 6,560 | $7.90 | $51,824 | 210,741 | Feb 15, 2024 |
| Hirsch Andrew | President & CEO | Award / Grant | 103,400 | — | — | 217,301 | Feb 14, 2024 |
| REYNO LEONARD | Chief Medical Officer | Award / Grant | 36,700 | — | — | 98,000 | Feb 14, 2024 |
| Siegel Jolie | Chief Legal Officer | Tax Withholding | 1,735 | $6.53 | $11,330 | 24,951 | Feb 14, 2024 |
| Schick Kelly | Chief People Officer | Tax Withholding | 1,735 | $6.53 | $11,330 | 24,951 | Feb 14, 2024 |
| Fisher Stewart | Chief Scientific Officer | Tax Withholding | 2,255 | $6.53 | $14,725 | 101,821 | Feb 14, 2024 |
| Boyle Scott N | Chief Business Officer | Tax Withholding | 1,735 | $6.53 | $11,330 | 25,030 | Feb 14, 2024 |
| Adams Kendra | Chief Financial Officer | Tax Withholding | 1,301 | $6.53 | $8,496 | 45,339 | Feb 14, 2024 |
| Mossler Mark | Chief Accounting Officer | Award / Grant | 18,290 | — | — | 19,790 | Feb 14, 2024 |