INSM
Insmed Inc
NASDAQ: INSM · HEALTHCARE · BIOTECHNOLOGY
$97.85
+1.17% today
Updated 2026-06-12
Market cap
$21.21B
P/E ratio
—
P/S ratio
25.88x
EPS (TTM)
$-5.76
Dividend yield
—
52W range
$90 – $213
Volume
3.0M
Insmed Inc (INSM) Insider transactions
Net insider activity
Net selling (243,823 shares)
Buy transactions
27
Sell transactions
73
All transactions
| Date | Insider | Title | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-06-05 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 1,858 | $103.78 | $192823.24 |
| 2026-06-03 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 2,159 | $102.27 | $220800.93 |
| 2026-06-03 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 7,605 | $102.27 | $777763.35 |
| 2026-06-03 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 2,566 | $102.27 | $262424.82 |
| 2026-06-03 | BONSTEIN, SARA | Chief Financial Officer | Sale | 2,404 | $102.27 | $245857.08 |
| 2026-06-03 | ADSETT, ROGER | Chief Operating Officer | Sale | 2,370 | $102.27 | $242379.90 |
| 2026-05-22 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 6,149 | $108.47 | $666982.03 |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 11,836 | $106.39 | $1.26M |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 7,975 | $106.97 | $853085.75 |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 5,753 | $105.32 | $605905.96 |
| 2026-05-18 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-05-14 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 10,479 | $117.54 | $1.23M |
| 2026-05-13 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 4,109 | $116.18 | $477383.62 |
| 2026-05-13 | SHAROKY, MELVIN MD | Director | Buy | 3,305 | — | — |
| 2026-05-13 | SCHAFER, CAROL | Director | Buy | 3,305 | — | — |
| 2026-05-13 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 13,283 | $116.18 | $1.54M |
| 2026-05-13 | LEE, LEO | Director | Buy | 3,305 | — | — |
| 2026-05-13 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 4,470 | $112.76 | $504037.20 |
| 2026-05-13 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 3,384 | $116.18 | $393153.12 |
| 2026-05-13 | DESJARDINS, CLARISSA | Director | Buy | 3,305 | — | — |
| 2026-05-13 | BRENNAN, DAVID R | Director | Buy | 3,305 | — | — |
| 2026-05-13 | BONSTEIN, SARA | Chief Financial Officer | Sale | 8,272 | $116.18 | $961040.96 |
| 2026-05-13 | ANDERSON, ELIZABETH M | Director | Buy | 3,305 | — | — |
| 2026-05-13 | ADSETT, ROGER | Chief Operating Officer | Sale | 5,837 | $116.18 | $678142.66 |
| 2026-05-11 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 12,949 | — | — |
| 2026-05-11 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Buy | 12,949 | $17.07 | $221039.43 |
| 2026-05-11 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 12,119 | $100.35 | $1.22M |
| 2026-05-11 | FLAMMER, MARTINA M.D. | Chief Medical Officer | Sale | 830 | $101.18 | $83979.40 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 5,318 | $137.01 | $728619.18 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,721 | $137.86 | $375117.06 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,247 | $139.09 | $173445.23 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 599 | $135.18 | $80972.82 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 433 | $134.18 | $58099.94 |
| 2026-05-04 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 381 | $139.60 | $53187.60 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 5,373 | $143.81 | $772691.13 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,255 | $144.66 | $326208.30 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,246 | $142.99 | $321155.54 |
| 2026-04-16 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 825 | $145.79 | $120276.75 |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 8,478 | $163.23 | $1.38M |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,434 | $164.01 | $235190.34 |
| 2026-04-06 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 787 | $161.73 | $127281.51 |
| 2026-04-01 | ADSETT, ROGER | Chief Operating Officer | Sale | 88,060 | — | — |
| 2026-04-01 | ADSETT, ROGER | Chief Operating Officer | Buy | 88,060 | $14.56 | $1.28M |
| 2026-04-01 | ADSETT, ROGER | Chief Operating Officer | Sale | 62,344 | $164.95 | $10.28M |
| 2026-04-01 | ADSETT, ROGER | Chief Operating Officer | Sale | 19,001 | $164.11 | $3.12M |
| 2026-04-01 | ADSETT, ROGER | Chief Operating Officer | Sale | 6,715 | $163.18 | $1.10M |
| 2026-03-30 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 13,989 | — | — |
| 2026-03-30 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 5,649 | — | — |
| 2026-03-30 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 19,638 | $150.98 | $2.96M |
| 2026-03-30 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Buy | 13,989 | $27.89 | $390153.21 |
| 2026-03-30 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Buy | 5,649 | $17.07 | $96428.43 |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,537 | $143.42 | $650696.54 |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,533 | $144.11 | $653250.63 |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-03-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,629 | $142.17 | $231594.93 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 3,899 | $146.66 | $571827.34 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,589 | $145.27 | $376104.03 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,128 | $147.54 | $313965.12 |
| 2026-03-05 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,083 | $144.23 | $300431.09 |
| 2026-03-03 | SHAROKY, MELVIN MD | Director | Sale | 100 | — | — |
| 2026-02-25 | SHAROKY, MELVIN MD | Director | Sale | 1,072 | — | — |
| 2026-02-25 | SHAROKY, MELVIN MD | Director | Buy | 243 | — | — |
| 2026-02-24 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 20,248 | — | — |
| 2026-02-24 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Buy | 20,248 | $17.07 | $345633.36 |
| 2026-02-24 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 15,771 | $156.53 | $2.47M |
| 2026-02-24 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 4,852 | $153.93 | $746868.36 |
| 2026-02-24 | SMITH, MICHAEL ALEXANDER | Chief Legal Officer | Sale | 4,151 | $155.06 | $643654.06 |
| 2026-02-23 | BRENNAN, DAVID R | Director | Sale | 6,000 | — | — |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 6,259 | — | — |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 4,440 | — | — |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 6,259 | $30.46 | $190649.14 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Buy | 4,440 | $17.16 | $76190.40 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 3,413 | $151.12 | $515772.56 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 2,377 | $151.92 | $361113.84 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,988 | $149.17 | $296549.96 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,891 | $150.10 | $283839.10 |
| 2026-02-19 | LEWIS, WILLIAM | Director, Chair and CEO | Sale | 1,030 | $153.38 | $157981.40 |
| 2026-02-09 | MCGIRR, DAVID W J | Director | Buy | 53,400 | — | — |
Frequently asked questions
Are INSM insiders buying or selling?
Over the transactions on record, INSM insiders have been net sellers, with about $43.21M in stock sold across 73 sales, against 19 open-market purchases.
Does insider selling at INSM mean the stock will fall?
Not by itself. Most executive selling is pre-scheduled through 10b5-1 plans filed months in advance, and insiders sell for diversification, taxes, and liquidity far more often than out of any view on the price. Insider buying is the stronger signal, especially when several insiders buy around the same time, because there is usually only one reason to put personal cash into the stock.
Which INSM insiders are selling the most?
Recent selling is concentrated in a few names. ADSETT, ROGER accounts for the largest share on record, with about $15.42M sold. Selling by one or two individuals matters less than broad selling across the whole leadership team, which is the pattern worth watching.