As of April 28, 2026, Insmed's top three insider holders are Steinar J Engelsen (Director, 320.80K shares), William Lewis (Chair And Ceo, 301.19K shares), William Lewis (Chair And Ceo, 301.19K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Steinar J Engelsen | - | 320,802 | 0 | 03 Nov, 2021 |
| William Lewis | Chair And Ceo | 301,185 | 0 | 20 Mar, 2026 |
| William Lewis | Chair And Ceo | 301,185 | 0 | 17 Apr, 2026 |
| William Lewis | Chair And Ceo | 301,185 | 0 | 08 Apr, 2026 |
| Melvin Md Sharoky | - | 242,776 | 0 | 05 Mar, 2026 |
| Melvin Md Sharoky | - | 242,776 | 0 | 05 Mar, 2026 |
| Melvin Md Sharoky | - | 242,776 | 0 | 05 Mar, 2026 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 20 Aug, 2025 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 31 Oct, 2023 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 20 Aug, 2025 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 31 Oct, 2023 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 20 Aug, 2025 |
| William Lewis | Chair And Ceo | 0 | 233,924 | 31 Oct, 2023 |
| John Drayton Wise | Chief Commercial Officer | 133,015 | 0 | 07 Feb, 2025 |
| John Drayton Wise | Chief Commercial Officer | 133,015 | 0 | 07 Feb, 2025 |
| John Drayton Wise | Chief Commercial Officer | 133,015 | 0 | 07 Feb, 2025 |
| Roger Adsett | Chief Operating Officer | 106,810 | 0 | 03 Apr, 2026 |
| John Drayton Wise | Chief Commercial Officer | 103,984 | 0 | 05 Jan, 2024 |
| John Drayton Wise | Chief Commercial Officer | 103,984 | 0 | 05 Jan, 2024 |
| John Drayton Wise | Chief Commercial Officer | 103,984 | 0 | 05 Jan, 2024 |
| David W J Mcgirr | - | 44,323 | 53,400 | 11 Feb, 2026 |
| David W J Mcgirr | - | 44,323 | 53,400 | 11 Feb, 2026 |
| Martina M.D. Flammer | Chief Medical Officer | 83,243 | 0 | 06 Feb, 2026 |
| Sara Bonstein | Chief Financial Officer | 79,758 | 0 | 04 Feb, 2026 |
| Alfred Altomari | - | 69,495 | 0 | 15 May, 2024 |
| Clarissa Desjardins | - | 67,007 | 0 | 19 May, 2025 |
| Carol Schafer | - | 63,317 | 0 | 19 May, 2025 |
| Carol Schafer | - | 63,317 | 0 | 19 May, 2025 |
| Carol Schafer | - | 63,317 | 0 | 19 May, 2025 |
| David R Brennan | - | 60,933 | 0 | 25 Feb, 2026 |
| David R Brennan | - | 0 | 60,000 | 10 Nov, 2025 |
| Elizabeth M Anderson | - | 58,729 | 0 | 26 Nov, 2025 |
| Leo Lee | - | 54,677 | 0 | 18 Nov, 2025 |
| Leo Lee | - | 54,677 | 0 | 18 Nov, 2025 |
| Leo Lee | - | 54,677 | 0 | 18 Nov, 2025 |
| Michael Alexander Smith | Chief Legal Officer | 51,871 | 0 | 31 Mar, 2026 |
| Michael Alexander Smith | Chief Legal Officer | 51,871 | 0 | 31 Mar, 2026 |
| Michael Alexander Smith | Chief Legal Officer | 51,871 | 0 | 31 Mar, 2026 |
| William Lewis | Chair And Ceo | 0 | 50,500 | 29 Feb, 2024 |
| William Lewis | Chair And Ceo | 0 | 50,500 | 29 Feb, 2024 |
| William Lewis | Chair And Ceo | 0 | 50,500 | 29 Feb, 2024 |
| Orlov S Nicole Schaeffer | Chief People Strategy Officer | 41,754 | 0 | 06 Jan, 2026 |
| Orlov S Nicole Schaeffer | Chief People Strategy Officer | 41,754 | 0 | 06 Jan, 2026 |
| Orlov S Nicole Schaeffer | Chief People Strategy Officer | 41,754 | 0 | 06 Jan, 2026 |
| John Soriano | Chief Compliance Officer | 35,204 | 0 | 09 Sep, 2021 |
| John Soriano | Chief Compliance Officer | 35,204 | 0 | 09 Sep, 2021 |
| John Soriano | Chief Compliance Officer | 35,204 | 0 | 09 Sep, 2021 |
| Melvin Md Sharoky | - | 0 | 17,714 | 03 Sep, 2024 |
| Melvin Md Sharoky | - | 0 | 17,714 | 03 Sep, 2024 |
| Melvin Md Sharoky | - | 0 | 17,714 | 03 Sep, 2024 |
| Melvin Md Sharoky | - | 0 | 15,900 | 02 Nov, 2022 |
| Melvin Md Sharoky | - | 0 | 15,900 | 02 Nov, 2022 |
| Melvin Md Sharoky | - | 0 | 15,900 | 02 Nov, 2022 |
| Melvin Md Sharoky | - | 0 | 14,973 | 27 Feb, 2026 |
| Melvin Md Sharoky | - | 0 | 14,973 | 27 Feb, 2026 |
| Melvin Md Sharoky | - | 0 | 14,973 | 27 Feb, 2026 |
| Melvin Md Sharoky | - | 0 | 10,000 | 17 May, 2023 |
| Melvin Md Sharoky | - | 0 | 10,000 | 17 May, 2023 |
| Melvin Md Sharoky | - | 0 | 10,000 | 17 May, 2023 |
| Melvin Md Sharoky | - | 0 | 6,847 | 14 Aug, 2025 |
| Melvin Md Sharoky | - | 0 | 6,847 | 14 Aug, 2025 |
| Melvin Md Sharoky | - | 0 | 6,847 | 14 Aug, 2025 |
| Clarissa Desjardins | - | 0 | 3,025 | 22 May, 2025 |
| Melvin Md Sharoky | - | 0 | 741 | 15 Sep, 2025 |
| Melvin Md Sharoky | - | 0 | 741 | 15 Sep, 2025 |
| Melvin Md Sharoky | - | 0 | 741 | 15 Sep, 2025 |
| Melvin Md Sharoky | - | 0 | 400 | 22 May, 2025 |
| Melvin Md Sharoky | - | 0 | 400 | 22 May, 2025 |
| Melvin Md Sharoky | - | 0 | 400 | 22 May, 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 | 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 | 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 | 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 | 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 | 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 | 6,259 | $0.00 | 43,814 | D | M |