INSM's three largest insider shareholders as of June 09, 2026 are Steinar J Engelsen (Director, 320.80K shares), William Lewis (Chair And Ceo, 301.19K shares), Melvin Md Sharoky (Director, 242.78K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Melvin Md Sharoky | - | 242,776 | 0 | 05 Mar, 2026 |
| Steinar J Engelsen | - | 320,802 | 0 | 03 Nov, 2021 |
| Carol Schafer | - | 63,317 | 0 | 19 May, 2025 |
| Alfred Altomari | - | 69,495 | 0 | 15 May, 2024 |
| Orlov S Nicole Schaeffer | Chief People Strategy Officer | 41,754 | 0 | 06 Jan, 2026 |
| William Lewis | Chair And Ceo | 301,185 | 0 | 17 Apr, 2026 |
| Sara Bonstein | Chief Financial Officer | 79,758 | 0 | 04 Feb, 2026 |
| David R Brennan | - | 60,933 | 0 | 25 Feb, 2026 |
| Roger Adsett | Chief Operating Officer | 106,810 | 0 | 03 Apr, 2026 |
| Leo Lee | - | 54,677 | 0 | 18 Nov, 2025 |
| John Soriano | Chief Compliance Officer | 35,204 | 0 | 09 Sep, 2021 |
| Elizabeth M Anderson | - | 58,729 | 0 | 26 Nov, 2025 |
| Clarissa Desjardins | - | 67,007 | 0 | 19 May, 2025 |
| Martina M.D. Flammer | Chief Medical Officer | 83,243 | 0 | 06 Feb, 2026 |
| Michael Alexander Smith | Chief Legal Officer | 51,871 | 0 | 31 Mar, 2026 |
| John Drayton Wise | Chief Commercial Officer | 133,015 | 0 | 07 Feb, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 16 Apr, 2026 | William Lewis | Common Stock | A | 6,259 | $30.46 | 307,444 | D | M |
| 16 Apr, 2026 | William Lewis | Common Stock | A | 4,440 | $17.16 | 311,884 | D | M |
| 16 Apr, 2026 | William Lewis | Common Stock | D | 2,246 | $142.99 | 309,638 | D | S |
| 16 Apr, 2026 | William Lewis | Common Stock | D | 5,373 | $143.81 | 304,265 | D | S |
| 16 Apr, 2026 | William Lewis | Common Stock | D | 2,255 | $144.66 | 302,010 | D | S |
| 16 Apr, 2026 | William Lewis | Common Stock | D | 825 | $145.79 | 301,185 | D | S |
| 16 Apr, 2026 | William Lewis | Stock Option (right to buy) | D | 6,259 | $0.00 | 37,555 | D | M |
| 16 Apr, 2026 | William Lewis | Stock Option (right to buy) | D | 4,440 | $0.00 | 26,640 | D | M |
| 06 Apr, 2026 | William Lewis | Common Stock | A | 6,259 | $30.46 | 307,444 | D | M |
| 06 Apr, 2026 | William Lewis | Common Stock | A | 4,440 | $17.16 | 311,884 | D | M |
| 06 Apr, 2026 | William Lewis | Common Stock | D | 787 | $161.73 | 311,097 | D | S |
| 06 Apr, 2026 | William Lewis | Common Stock | D | 8,478 | $163.23 | 302,619 | D | S |
| 06 Apr, 2026 | William Lewis | Common Stock | D | 1,434 | $164.01 | 301,185 | D | S |
| 06 Apr, 2026 | William Lewis | Stock Option (right to buy) | D | 6,259 | $0.00 | 43,814 | D | M |
| 06 Apr, 2026 | William Lewis | Stock Option (right to buy) | D | 4,440 | $0.00 | 31,080 | D | M |
| 01 Apr, 2026 | Roger Adsett | Common Stock | A | 88,060 | $14.56 | 194,870 | D | M |
| 01 Apr, 2026 | Roger Adsett | Common Stock | D | 6,715 | $163.18 | 188,155 | D | S |
| 01 Apr, 2026 | Roger Adsett | Common Stock | D | 19,001 | $164.11 | 169,154 | D | S |
| 01 Apr, 2026 | Roger Adsett | Common Stock | D | 62,344 | $164.95 | 106,810 | D | S |
| 01 Apr, 2026 | Roger Adsett | Stock Option (right to buy) | D | 88,060 | $0.00 | 0 | D | M |