Insider Ledger
Insmed Inc. (INSM) insider buying and SEC filings
Insmed Inc. · CIK 1104506
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Company profile
- Exchanges
- Nasdaq
- Industry (SIC)
- Pharmaceutical Preparations
- State of incorporation
- VA
- Fiscal year end
- Dec 31
Insider activity in the last 12 months
Bought
$0
Insiders who bought
0
Sold (not marked 10b5-1)
$35.3M
Planned sales (10b5-1)
$94.1M
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Sep 9, 2026 | Sale | David R Brennan (Director) sold 25,000 shares at $124.00 ($3.1M). Holdings down 39% to 39,238 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 11, 2026 |
| Aug 17, 2026 | Sale | Melvin Md Sharoky (Director) sold 5,000 shares indirectly (by entity) at about $127.53 ($638K). Holdings by entity down 100% to 0 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Aug 19, 2026 |
| Aug 6, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 27,173 shares at about $128.61 ($3.5M), marked as a 10b5-1 plan trade. Holdings down 31% to 60,486 shares. | SEC filing Filed Aug 7, 2026 |
| Jul 23, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,700 shares at about $106.06 ($1.1M), marked as a 10b5-1 plan trade. Holdings down 4% to 259,058 shares. | SEC filing Filed Jul 24, 2026 |
| Jul 9, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $117.40 ($1.3M), marked as a 10b5-1 plan trade. Holdings down 4% to 259,058 shares. | SEC filing Filed Jul 10, 2026 |
| Jul 6, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 12,302 shares at about $109.98 ($1.4M), marked as a 10b5-1 plan trade. Holdings down 17% to 60,486 shares. | SEC filing Filed Jul 8, 2026 |
| Jun 25, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 21,398 shares at about $103.32 ($2.2M), marked as a 10b5-1 plan trade. Holdings down 8% to 258,917 shares. | SEC filing Filed Jun 26, 2026 |
| Jun 22, 2026 | Planned (10b5-1) | Michael Alexander Smith (Chief Legal Officer) sold 1,806 shares at $95.82 ($173K), marked as a 10b5-1 plan trade. Holdings down 5% to 37,648 shares. | SEC filing Filed Jun 24, 2026 |
| Jun 8, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 6,515 shares at $94.03 ($613K), marked as a 10b5-1 plan trade. Holdings down 2% to 258,917 shares. | SEC filing Filed Jun 10, 2026 |
| Jun 3, 2026 | Sale | Michael Alexander Smith (Chief Legal Officer) sold 2,159 shares at $102.27 ($221K). Holdings down 5% to 39,454 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 5, 2026 |
| Jun 3–5, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 4,424 shares between Jun 3 and Jun 5 at about $102.90 ($455K), marked as a 10b5-1 plan trade. Holdings down 7% to 60,486 shares. | SEC filing Filed Jun 5, 2026 |
| Jun 3, 2026 | Sale | Roger Adsett (President / COO) sold 2,370 shares at $102.27 ($242K). Holdings down 2% to 98,603 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 5, 2026 |
| Jun 3, 2026 | Sale | Sara Bonstein (CFO) sold 2,404 shares at $102.27 ($246K). Holdings down 3% to 69,082 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 5, 2026 |
| Jun 3, 2026 | Sale | William Lewis (CEO and Director) sold 7,605 shares at $102.27 ($778K). Holdings down 3% to 265,432 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 5, 2026 |
| May 22, 2026 | Planned (10b5-1) | Michael Alexander Smith (Chief Legal Officer) sold 6,149 shares at $108.47 ($667K), marked as a 10b5-1 plan trade. Holdings down 13% to 41,613 shares. | SEC filing Filed May 22, 2026 |
| May 18, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 25,564 shares at about $106.33 ($2.7M), marked as a 10b5-1 plan trade. Holdings down 9% to 273,037 shares. | SEC filing Filed May 20, 2026 |
| May 13, 2026 | Sale | Michael Alexander Smith (Chief Legal Officer) sold 4,109 shares at $116.18 ($477K). Holdings down 8% to 47,762 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 13–14, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 18,333 shares between May 13 and May 14 at about $116.12 ($2.1M), marked as a 10b5-1 plan trade. Holdings down 22% to 64,910 shares. | SEC filing Filed May 15, 2026 |
| May 13, 2026 | Sale | Roger Adsett (President / COO) sold 5,837 shares at $116.18 ($678K). Holdings down 5% to 100,973 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 13, 2026 | Sale | Sara Bonstein (CFO) sold 8,272 shares at $116.18 ($961K). Holdings down 10% to 71,486 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 13, 2026 | Sale | William Lewis (CEO and Director) sold 13,283 shares at $116.18 ($1.5M). Holdings down 4% to 287,902 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 11, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 12,949 shares at about $100.40 ($1.3M), marked as a 10b5-1 plan trade. Holdings down 13% to 83,243 shares. | SEC filing Filed May 13, 2026 |
| May 4, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $137.34 ($1.5M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed May 6, 2026 |
| Apr 16, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $143.97 ($1.5M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed Apr 17, 2026 |
| Apr 6, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $163.22 ($1.7M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed Apr 8, 2026 |
| Apr 1, 2026 | Planned (10b5-1) | Roger Adsett (President / COO) sold 88,060 shares at about $164.63 ($14.5M), marked as a 10b5-1 plan trade. Holdings down 45% to 106,810 shares. | SEC filing Filed Apr 3, 2026 |
| Mar 30, 2026 | Planned (10b5-1) | Michael Alexander Smith (Chief Legal Officer) sold 19,638 shares at $150.98 ($3.0M), marked as a 10b5-1 plan trade. Holdings down 27% to 51,871 shares. | SEC filing Filed Mar 31, 2026 |
| Mar 19, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $143.52 ($1.5M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed Mar 20, 2026 |
| Mar 5, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $146.03 ($1.6M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed Mar 5, 2026 |
| Feb 24, 2026 | Planned (10b5-1) | Michael Alexander Smith (Chief Legal Officer) sold 24,774 shares at about $155.77 ($3.9M), marked as a 10b5-1 plan trade. Holdings down 32% to 51,871 shares. | SEC filing Filed Feb 25, 2026 |
| Feb 19, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $150.97 ($1.6M), marked as a 10b5-1 plan trade. Holdings down 3% to 301,185 shares. | SEC filing Filed Feb 23, 2026 |
| Feb 9, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 13,396 shares at about $147.79 ($2.0M), marked as a 10b5-1 plan trade. Holdings down 4% to 301,185 shares. | SEC filing Filed Feb 11, 2026 |
| Feb 5, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 869 shares at $152.44 ($132K), marked as a 10b5-1 plan trade. Holdings down 1% to 83,243 shares. | SEC filing Filed Feb 6, 2026 |
| Feb 3, 2026 | Sale | Michael Alexander Smith (Chief Legal Officer) sold 640 shares at $156.27 ($100K). Holdings down 1% to 56,397 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 4, 2026 |
| Feb 3, 2026 | Sale | Roger Adsett (President / COO) sold 791 shares at $156.17 ($124K). Holdings down 1% to 106,810 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 4, 2026 |
| Feb 3, 2026 | Sale | Sara Bonstein (CFO) sold 748 shares at $156.34 ($117K). Holdings down 1% to 79,758 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 4, 2026 |
| Feb 3, 2026 | Sale | William Lewis (CEO and Director) sold 3,009 shares at $156.34 ($470K). Holdings down 1% to 303,882 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 4, 2026 |
| Feb 2–3, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 8,777 shares between Feb 2 and Feb 3 at about $154.70 ($1.4M), marked as a 10b5-1 plan trade. Holdings down 9% to 84,112 shares. | SEC filing Filed Feb 4, 2026 |
| Jan 20, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $158.93 ($1.7M), marked as a 10b5-1 plan trade. Holdings down 3% to 306,891 shares. | SEC filing Filed Jan 22, 2026 |
| Jan 12, 2026 | Planned (10b5-1) | William Lewis (CEO and Director) sold 19,215 shares at about $169.00 ($3.2M), marked as a 10b5-1 plan trade. Holdings down 6% to 306,891 shares. | SEC filing Filed Jan 13, 2026 |
| Jan 9, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 1,887 shares at $186.19 ($351K), marked as a 10b5-1 plan trade. Holdings down 2% to 84,907 shares. | SEC filing Filed Jan 13, 2026 |
| Jan 6–8, 2026 | Sale | Michael Alexander Smith (Chief Legal Officer) sold 3,158 shares between Jan 6 and Jan 8 at about $174.00 ($549K). Holdings down 5% to 57,037 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 8, 2026 |
| Jan 6–8, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 16,530 shares between Jan 6 and Jan 8 at about $174.06 ($2.9M), marked as a 10b5-1 plan trade. Holdings down 16% to 86,794 shares. | SEC filing Filed Jan 8, 2026 |
| Jan 6–8, 2026 | Sale | Roger Adsett (President / COO) sold 4,290 shares between Jan 6 and Jan 8 at about $174.06 ($747K). Holdings down 4% to 107,601 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 8, 2026 |
| Jan 6–8, 2026 | Sale | Sara Bonstein (CFO) sold 4,642 shares between Jan 6 and Jan 8 at about $174.22 ($809K). Holdings down 5% to 80,506 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 8, 2026 |
| Jan 6–8, 2026 | Sale | William Lewis (CEO and Director) sold 9,676 shares between Jan 6 and Jan 8 at about $174.03 ($1.7M). Holdings down 3% to 315,407 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 8, 2026 |
| Jan 5, 2026 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 12,303 shares at about $171.38 ($2.1M), marked as a 10b5-1 plan trade. Holdings down 11% to 94,754 shares. | SEC filing Filed Jan 6, 2026 |
| Jan 2, 2026 | Planned (10b5-1) | Orlov S Nicole Schaeffer (Chief People Strategy Officer) sold 87,290 shares at about $175.20 ($15.3M), marked as a 10b5-1 plan trade. Holdings down 68% to 41,754 shares. | SEC filing Filed Jan 6, 2026 |
| Dec 18, 2025 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $166.97 ($1.8M), marked as a 10b5-1 plan trade. Holdings down 3% to 303,911 shares. | SEC filing Filed Dec 19, 2025 |
| Dec 5, 2025 | Sale | Melvin Md Sharoky (Director) sold 20,000 shares at about $205.01 ($4.1M). Holdings down 8% to 243,948 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Dec 9, 2025 |
| Dec 4, 2025 | Planned (10b5-1) | William Lewis (CEO and Director) sold 10,699 shares at about $205.62 ($2.2M), marked as a 10b5-1 plan trade. Holdings down 3% to 303,911 shares. | SEC filing Filed Dec 5, 2025 |
| Dec 1, 2025 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 8,895 shares at about $206.98 ($1.8M), marked as a 10b5-1 plan trade. Holdings down 10% to 83,111 shares. | SEC filing Filed Dec 3, 2025 |
| Nov 24, 2025 | Sale | Elizabeth M. Anderson (Director) sold 5,000 shares at $204.58 ($1.0M). Holdings down 8% to 58,729 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 26, 2025 |
| Nov 17, 2025 | Sale | Leo Lee (Director) sold 75,000 shares at about $195.90 ($14.7M). Holdings down 58% to 54,677 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 18, 2025 |
| Nov 14, 2025 | Sale | Elizabeth M. Anderson (Director) sold 10,000 shares at $195.87 ($2.0M). Holdings down 14% to 63,729 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 18, 2025 |
| Nov 11, 2025 | Planned (10b5-1) | Martina M.D. Flammer (Chief Medical Officer) sold 31,226 shares at about $189.68 ($5.9M), marked as a 10b5-1 plan trade. Holdings down 27% to 83,111 shares. | SEC filing Filed Nov 13, 2025 |
| Nov 3, 2025 | Planned (10b5-1) | Michael Alexander Smith (Chief Legal Officer) sold 27,130 shares at about $183.78 ($5.0M), marked as a 10b5-1 plan trade. Holdings down 33% to 54,902 shares. | SEC filing Filed Nov 5, 2025 |
50 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
No cluster buys in the last 12 months.
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
| Filed | Items | Tag | Source |
|---|---|---|---|
| Oct 29, 2026, 7:01 AM ET 8-K | Earnings released (Item 2.02) | SEC filing |
Red flags are objective triggers only: the item or form filed, never an opinion.
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