Insmed (INSM)
Insmed on one page: short interest, daily short volume, fails to deliver, planned sales, large holders, 13F holders, financials, earnings dates and insider trades. Listed on Nasdaq, classified by the SEC as pharmaceutical preparations.
13.5M
Short interest
settlement 2026-10-15
4.1
Days to cover
-2.4 days vs prior
47.8%
Short share of volume
2026-10-28
30
Fails to deliver
settlement 2026-09-25
Thu 29 Oct
Next earnings
estimated date
-$39.2M
Insider flow, 90 days
0 buys, 5 sells
As of 2026-10-28.
Short interest
FINRA, twice a month. The newest 48 settlements in the table, 48 in the chart. JSONAs of 15 October 2026, short interest in INSM is 13,477,593 shares, up 2,675,523 shares over the last month. Over the last 48 readings it ranged from 8,033,501 shares (31 October 2025) to 19,132,984 shares (29 May 2026). At the reported average volume of 3.3M shares a day that is 4.1 days to cover.
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| Settlement | Shares short | Change | Avg daily volume | Days to cover |
|---|---|---|---|---|
| 2026-10-15 | 13,477,593 | -2.3% | 3,261,711 | 4.13 |
| 2026-09-30 | 13,800,693 | +27.8% | 2,123,248 | 6.50 |
| 2026-09-15 | 10,802,070 | -5.6% | 2,049,480 | 5.27 |
| 2026-08-31 | 11,440,176 | +5.0% | 1,668,674 | 6.86 |
| 2026-08-14 | 10,892,278 | -4.0% | 4,091,987 | 2.66 |
| 2026-07-31 | 11,350,580 | -2.4% | 2,207,650 | 5.14 |
| 2026-07-15 | 11,624,756 | -27.5% | 2,440,598 | 4.76 |
| 2026-06-30 | 16,030,053 | -14.0% | 5,800,443 | 2.76 |
| 2026-06-15 | 18,647,626 | -2.5% | 4,164,071 | 4.48 |
| 2026-05-29 | 19,132,984 | +8.7% | 3,132,399 | 6.11 |
| 2026-05-15 | 17,606,497 | +19.7% | 5,214,392 | 3.38 |
| 2026-04-30 | 14,709,273 | +6.2% | 1,581,263 | 9.30 |
| 2026-04-15 | 13,855,201 | +0.7% | 1,988,756 | 6.97 |
| 2026-03-31 | 13,756,534 | +37.0% | 2,950,831 | 4.66 |
| 2026-03-13 | 10,037,946 | -11.0% | 1,900,481 | 5.28 |
| 2026-02-27 | 11,279,030 | -1.8% | 2,563,846 | 4.40 |
| 2026-02-13 | 11,489,389 | -1.8% | 2,178,016 | 5.28 |
| 2026-01-30 | 11,703,014 | -1.6% | 2,459,116 | 4.76 |
| 2026-01-15 | 11,887,857 | +7.9% | 2,819,796 | 4.22 |
| 2025-12-31 | 11,015,687 | +23.4% | 4,718,921 | 2.33 |
| 2025-12-15 | 8,927,430 | -9.5% | 2,382,751 | 3.75 |
| 2025-11-28 | 9,866,791 | +10.5% | 3,498,565 | 2.82 |
| 2025-11-14 | 8,927,374 | +11.1% | 2,074,508 | 4.30 |
| 2025-10-31 | 8,033,501 | -15.3% | 2,281,258 | 3.52 |
| 2025-10-15 | 9,481,459 | -11.6% | 1,915,903 | 4.95 |
| 2025-09-30 | 10,727,695 | +1.4% | 2,288,187 | 4.69 |
| 2025-09-15 | 10,575,467 | +0.1% | 2,176,773 | 4.86 |
| 2025-08-29 | 10,563,132 | +0.6% | 2,224,281 | 4.75 |
| 2025-08-15 | 10,496,754 | +10.1% | 3,693,168 | 2.84 |
| 2025-07-31 | 9,537,045 | -1.6% | 2,210,108 | 4.32 |
| 2025-07-15 | 9,688,399 | -1.1% | 2,838,230 | 3.41 |
| 2025-06-30 | 9,796,337 | -15.9% | 6,772,593 | 1.45 |
| 2025-06-13 | 11,650,625 | -33.3% | 5,334,698 | 2.18 |
| 2025-05-30 | 17,458,827 | +6.0% | 2,400,841 | 7.27 |
| 2025-05-15 | 16,467,942 | +4.4% | 2,133,596 | 7.72 |
| 2025-04-30 | 15,778,659 | +4.4% | 3,099,609 | 5.09 |
| 2025-04-15 | 15,120,119 | +4.3% | 2,781,941 | 5.44 |
| 2025-03-31 | 14,503,271 | +0.3% | 1,381,186 | 10.50 |
| 2025-03-14 | 14,466,895 | -1.0% | 1,892,091 | 7.65 |
| 2025-02-28 | 14,615,125 | +1.0% | 2,133,350 | 6.85 |
| 2025-02-14 | 14,464,983 | -0.5% | 1,609,974 | 8.98 |
| 2025-01-31 | 14,539,067 | -3.6% | 1,875,720 | 7.75 |
| 2025-01-15 | 15,089,466 | -2.3% | 2,097,551 | 7.19 |
| 2024-12-31 | 15,440,877 | +18.7% | 1,790,054 | 8.63 |
| 2024-12-13 | 13,010,105 | +3.1% | 1,697,010 | 7.67 |
| 2024-11-29 | 12,616,116 | +4.3% | 1,522,332 | 8.29 |
| 2024-11-15 | 12,100,491 | -12.6% | 1,675,870 | 7.22 |
| 2024-10-31 | 13,850,026 | +1.1% | 1,102,480 | 12.56 |
Daily short volume
FINRA Reg SHO, the last 30 sessions. JSONAs of 28 October 2026, the short share of INSM volume is 47.8%, up 18.9 points over the last five sessions. Over the last 30 readings it ranged from 21.9% (19 October 2026) to 69.5% (18 September 2026). The latest reading is 6.8 points above the 30-session average of 41.0%, on 2.1M shares reported.
| Date | Short volume | Total volume | Short share | Exempt |
|---|---|---|---|---|
| 2026-10-28 | 994K | 2.1M | 47.8% | 0 |
| 2026-10-27 | 522K | 1.4M | 37.6% | 1,687 |
| 2026-10-26 | 815K | 1.6M | 51.2% | 240 |
| 2026-10-23 | 608K | 1.3M | 47.0% | 31 |
| 2026-10-22 | 336K | 1.3M | 25.7% | 0 |
| 2026-10-21 | 324K | 1.1M | 28.9% | 53 |
| 2026-10-20 | 435K | 1.1M | 40.0% | 0 |
| 2026-10-19 | 216K | 987K | 21.9% | 0 |
| 2026-10-16 | 291K | 974K | 29.9% | 110 |
| 2026-10-15 | 867K | 1.8M | 47.3% | 76,806 |
| 2026-10-14 | 495K | 1.2M | 40.5% | 111 |
| 2026-10-13 | 412K | 893K | 46.2% | 3,565 |
| 2026-10-12 | 303K | 790K | 38.3% | 57 |
| 2026-10-09 | 285K | 1.1M | 26.9% | 1 |
| 2026-10-08 | 488K | 1.8M | 27.4% | 1,530 |
| 2026-10-07 | 316K | 1.0M | 30.2% | 0 |
| 2026-10-06 | 911K | 1.8M | 51.0% | 1,155 |
| 2026-10-05 | 1.4M | 2.7M | 53.9% | 34 |
| 2026-10-02 | 457K | 1.6M | 29.2% | 0 |
| 2026-10-01 | 397K | 1.1M | 34.9% | 0 |
| 2026-09-30 | 432K | 969K | 44.6% | 0 |
| 2026-09-29 | 379K | 798K | 47.5% | 583 |
| 2026-09-28 | 263K | 712K | 36.9% | 0 |
| 2026-09-25 | 481K | 1.5M | 32.6% | 35,368 |
| 2026-09-24 | 560K | 1.2M | 46.2% | 90 |
| 2026-09-23 | 291K | 925K | 31.5% | 1,972 |
| 2026-09-22 | 343K | 851K | 40.3% | 100 |
| 2026-09-21 | 545K | 896K | 60.8% | 0 |
| 2026-09-18 | 749K | 1.1M | 69.5% | 0 |
| 2026-09-17 | 467K | 729K | 64.0% | 0 |
Fails to deliver
SEC, the last 30 settlement dates with a fail. JSONAs of 25 September 2026, the fails-to-deliver balance in INSM is 30 shares, down 757 shares over the last settlement date. Over the last 30 readings it ranged from 1 share (30 July 2026) to 224,501 shares (8 May 2026). The latest reading sits at the bottom of that range.
| Settlement | Shares failed | Price | Value |
|---|---|---|---|
| 2026-09-25 | 30 | $121.55 | $4K |
| 2026-09-21 | 787 | $120.00 | $94K |
| 2026-09-18 | 88 | $123.98 | $11K |
| 2026-09-17 | 3,154 | $122.58 | $387K |
| 2026-09-03 | 152 | $126.63 | $19K |
| 2026-08-24 | 18,985 | $125.77 | $2.4M |
| 2026-08-06 | 112 | $99.02 | $11K |
| 2026-08-03 | 1,370 | $98.60 | $135K |
| 2026-07-30 | 1 | $103.12 | $103 |
| 2026-07-17 | 407 | $107.46 | $44K |
| 2026-07-13 | 9,169 | $115.61 | $1.1M |
| 2026-07-01 | 297 | $106.62 | $32K |
| 2026-06-29 | 434 | $103.38 | $45K |
| 2026-06-26 | 2,267 | $104.47 | $237K |
| 2026-06-25 | 166 | $103.46 | $17K |
| 2026-06-22 | 96 | $95.80 | $9K |
| 2026-06-18 | 5 | $98.45 | $492 |
| 2026-06-15 | 105 | $97.85 | $10K |
| 2026-06-11 | 43 | $91.88 | $4K |
| 2026-06-08 | 9,904 | $94.22 | $933K |
| 2026-06-04 | 48 | $103.86 | $5K |
| 2026-05-21 | 22,069 | $107.91 | $2.4M |
| 2026-05-13 | 11,691 | $116.00 | $1.4M |
| 2026-05-08 | 224,501 | $105.00 | $23.6M |
| 2026-04-20 | 139,933 | $144.48 | $20.2M |
| 2026-04-16 | 3 | $146.74 | $440 |
| 2026-04-09 | 358 | $160.18 | $57K |
| 2026-04-06 | 6 | $162.43 | $975 |
| 2026-03-23 | 7 | $136.00 | $952 |
| 2026-03-10 | 206 | $143.13 | $29K |
Insider trades
SEC Form 4, newest first. JSONInsiders at INSM reported 5 open-market sells worth $39.2M in the last 90 days and no open-market buys. Latest filing: Hudson Paul (Director) on 2026-10-19.
| Date | Insider | Title | Type | Shares | Price | Value | Owned after |
|---|---|---|---|---|---|---|---|
| 2026-10-19 | Hudson Paul | Director | Grant | 6K | price not stated in the filing | not stated | 6K |
| 2026-10-19 | Koppikar Utpal | Director | Grant | 6K | price not stated in the filing | not stated | 6K |
| 2026-09-09 | Brennan David R | Director | Sell | 25K | $124.00 | $3.1M | 39K |
| 2026-08-17 | SHAROKY MELVIN MD | Director | Sell | 5K | $127.53 | $638K | 0 |
| 2026-08-10 | Adsett Roger | Chief Operating Officer | Sell | 240K | $133.27 | $32.0M | 99K |
| 2026-08-10 | Adsett Roger | Chief Operating Officer | Exercise or conversion | 81K | $30.46 | $2.5M | 339K |
| 2026-08-10 | Adsett Roger | Chief Operating Officer | Exercise or conversion | 77K | $17.16 | $1.3M | 258K |
| 2026-08-10 | Adsett Roger | Chief Operating Officer | Exercise or conversion | 82K | $13.67 | $1.1M | 181K |
| 2026-08-06 | Flammer Martina M.D. | Chief Medical Officer | Sell | 18K | $129.40 | $2.4M | 60K |
| 2026-08-06 | Flammer Martina M.D. | Chief Medical Officer | Sell | 9K | $127.00 | $1.1M | 79K |
| 2026-08-06 | Flammer Martina M.D. | Chief Medical Officer | Exercise or conversion | 9K | $25.83 | $230K | 88K |
| 2026-08-06 | Flammer Martina M.D. | Chief Medical Officer | Exercise or conversion | 18K | $18.95 | $346K | 79K |
| 2026-07-23 | Lewis William | Chair and CEO | Sell | 6K | $106.43 | $625K | 259K |
| 2026-07-23 | Lewis William | Chair and CEO | Sell | 5K | $105.62 | $510K | 265K |
| 2026-07-23 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 270K |
| 2026-07-23 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 265K |
| 2026-07-09 | Lewis William | Chair and CEO | Sell | 3K | $118.52 | $398K | 259K |
| 2026-07-09 | Lewis William | Chair and CEO | Sell | 2K | $117.62 | $275K | 262K |
| 2026-07-09 | Lewis William | Chair and CEO | Sell | 5K | $116.55 | $583K | 265K |
| 2026-07-09 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 270K |
| 2026-07-09 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 265K |
| 2026-07-06 | Flammer Martina M.D. | Chief Medical Officer | Sell | 7K | $110.60 | $824K | 60K |
| 2026-07-06 | Flammer Martina M.D. | Chief Medical Officer | Sell | 5K | $109.02 | $529K | 68K |
| 2026-07-06 | Flammer Martina M.D. | Chief Medical Officer | Exercise or conversion | 4K | $19.74 | $86K | 73K |
| 2026-07-06 | Flammer Martina M.D. | Chief Medical Officer | Exercise or conversion | 8K | $29.13 | $231K | 68K |
| 2026-06-25 | Lewis William | Chair and CEO | Exercise or conversion | 13K | $30.46 | $381K | 271K |
| 2026-06-25 | Lewis William | Chair and CEO | Exercise or conversion | 9K | $17.16 | $152K | 280K |
| 2026-06-25 | Lewis William | Chair and CEO | Sell | 12K | $102.34 | $1.2M | 268K |
| 2026-06-25 | Lewis William | Chair and CEO | Sell | 2K | $103.10 | $189K | 266K |
| 2026-06-25 | Lewis William | Chair and CEO | Sell | 4K | $104.28 | $388K | 263K |
| 2026-06-25 | Lewis William | Chair and CEO | Sell | 2K | $105.27 | $259K | 260K |
| 2026-06-25 | Lewis William | Chair and CEO | Sell | 1K | $106.27 | $137K | 259K |
| 2026-06-23 | Butera Samuele | SVP, GM, Global Respiratory | Grant | 7K | price not stated in the filing | not stated | 7K |
| 2026-06-22 | Smith Michael Alexander | Chief Legal Officer | Sell | 2K | $95.82 | $173K | 38K |
| 2026-06-08 | Lewis William | Chair and CEO | Sell | 7K | $94.03 | $613K | 259K |
| 2026-06-05 | Flammer Martina M.D. | Chief Medical Officer | Sell | 2K | $103.78 | $193K | 60K |
| 2026-06-03 | Smith Michael Alexander | Chief Legal Officer | Sell | 2K | $102.27 | $221K | 39K |
| 2026-06-03 | Lewis William | Chair and CEO | Sell | 8K | $102.27 | $778K | 265K |
| 2026-06-03 | Flammer Martina M.D. | Chief Medical Officer | Sell | 3K | $102.27 | $262K | 62K |
| 2026-06-03 | Bonstein Sara | Chief Financial Officer | Sell | 2K | $102.27 | $246K | 69K |
| 2026-06-03 | Adsett Roger | Chief Operating Officer | Sell | 2K | $102.27 | $242K | 99K |
| 2026-05-22 | Smith Michael Alexander | Chief Legal Officer | Sell | 6K | $108.47 | $667K | 42K |
| 2026-05-18 | Lewis William | Chair and CEO | Sell | 8K | $106.97 | $853K | 273K |
| 2026-05-18 | Lewis William | Chair and CEO | Sell | 12K | $106.39 | $1.3M | 281K |
| 2026-05-18 | Lewis William | Chair and CEO | Sell | 6K | $105.32 | $606K | 293K |
| 2026-05-18 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 299K |
| 2026-05-18 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 294K |
| 2026-05-14 | Flammer Martina M.D. | Chief Medical Officer | Sell | 10K | $117.54 | $1.2M | 65K |
| 2026-05-13 | LEE LEO | Director | Grant | 3K | price not stated in the filing | not stated | 58K |
| 2026-05-13 | Desjardins Clarissa | Director | Grant | 3K | price not stated in the filing | not stated | 70K |
| 2026-05-13 | Brennan David R | Director | Grant | 3K | price not stated in the filing | not stated | 64K |
| 2026-05-13 | SHAROKY MELVIN MD | Director | Grant | 3K | price not stated in the filing | not stated | 246K |
| 2026-05-13 | ANDERSON ELIZABETH M | Director | Grant | 3K | price not stated in the filing | not stated | 62K |
| 2026-05-13 | SCHAFER CAROL | Director | Grant | 3K | price not stated in the filing | not stated | 67K |
| 2026-05-13 | Smith Michael Alexander | Chief Legal Officer | Sell | 4K | $116.18 | $477K | 48K |
| 2026-05-13 | Lewis William | Chair and CEO | Sell | 13K | $116.18 | $1.5M | 288K |
| 2026-05-13 | Flammer Martina M.D. | Chief Medical Officer | Sell | 3K | $116.18 | $393K | 75K |
| 2026-05-13 | Flammer Martina M.D. | Chief Medical Officer | Sell | 4K | $112.76 | $504K | 79K |
| 2026-05-13 | Bonstein Sara | Chief Financial Officer | Sell | 8K | $116.18 | $961K | 71K |
| 2026-05-13 | Adsett Roger | Chief Operating Officer | Sell | 6K | $116.18 | $678K | 101K |
| 2026-05-11 | Flammer Martina M.D. | Chief Medical Officer | Sell | 830 | $101.18 | $84K | 83K |
| 2026-05-11 | Flammer Martina M.D. | Chief Medical Officer | Sell | 12K | $100.35 | $1.2M | 84K |
| 2026-05-11 | Flammer Martina M.D. | Chief Medical Officer | Exercise or conversion | 13K | $17.07 | $221K | 96K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 381 | $139.60 | $53K | 301K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 1K | $139.09 | $173K | 302K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 3K | $137.86 | $375K | 303K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 5K | $137.01 | $729K | 306K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 599 | $135.18 | $81K | 311K |
| 2026-05-04 | Lewis William | Chair and CEO | Sell | 433 | $134.18 | $58K | 311K |
| 2026-05-04 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 312K |
| 2026-05-04 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 307K |
| 2026-04-16 | Lewis William | Chair and CEO | Sell | 825 | $145.79 | $120K | 301K |
| 2026-04-16 | Lewis William | Chair and CEO | Sell | 2K | $144.66 | $326K | 302K |
| 2026-04-16 | Lewis William | Chair and CEO | Sell | 5K | $143.81 | $773K | 304K |
| 2026-04-16 | Lewis William | Chair and CEO | Sell | 2K | $142.99 | $321K | 310K |
| 2026-04-16 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 312K |
| 2026-04-16 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 307K |
| 2026-04-06 | Lewis William | Chair and CEO | Sell | 1K | $164.01 | $235K | 301K |
| 2026-04-06 | Lewis William | Chair and CEO | Sell | 8K | $163.23 | $1.4M | 303K |
| 2026-04-06 | Lewis William | Chair and CEO | Sell | 787 | $161.73 | $127K | 311K |
| 2026-04-06 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 312K |
| 2026-04-06 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 307K |
| 2026-04-01 | Adsett Roger | Chief Operating Officer | Sell | 62K | $164.95 | $10.3M | 107K |
| 2026-04-01 | Adsett Roger | Chief Operating Officer | Sell | 19K | $164.11 | $3.1M | 169K |
| 2026-04-01 | Adsett Roger | Chief Operating Officer | Sell | 7K | $163.18 | $1.1M | 188K |
| 2026-04-01 | Adsett Roger | Chief Operating Officer | Exercise or conversion | 88K | $14.56 | $1.3M | 195K |
| 2026-03-30 | Smith Michael Alexander | Chief Legal Officer | Sell | 20K | $150.98 | $3.0M | 52K |
| 2026-03-30 | Smith Michael Alexander | Chief Legal Officer | Exercise or conversion | 14K | $27.89 | $390K | 72K |
| 2026-03-30 | Smith Michael Alexander | Chief Legal Officer | Exercise or conversion | 6K | $17.07 | $96K | 58K |
| 2026-03-19 | Lewis William | Chair and CEO | Sell | 5K | $144.11 | $653K | 301K |
| 2026-03-19 | Lewis William | Chair and CEO | Sell | 5K | $143.42 | $651K | 306K |
| 2026-03-19 | Lewis William | Chair and CEO | Sell | 2K | $142.17 | $232K | 310K |
| 2026-03-19 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 312K |
| 2026-03-19 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 307K |
| 2026-03-05 | Lewis William | Chair and CEO | Sell | 2K | $147.54 | $314K | 301K |
| 2026-03-05 | Lewis William | Chair and CEO | Sell | 4K | $146.66 | $572K | 303K |
| 2026-03-05 | Lewis William | Chair and CEO | Sell | 3K | $145.27 | $376K | 307K |
| 2026-03-05 | Lewis William | Chair and CEO | Sell | 2K | $144.23 | $300K | 310K |
| 2026-03-05 | Lewis William | Chair and CEO | Exercise or conversion | 4K | $17.16 | $76K | 312K |
| 2026-03-05 | Lewis William | Chair and CEO | Exercise or conversion | 6K | $30.46 | $191K | 307K |
Form 4 filings are due within two business days of the trade. Insiders sell for many reasons that say nothing about the company; open-market buys are rarer.
Planned sales (Form 144)
Newest first. JSON46 Form 144 notices on file for INSM worth $108.6M at the prices reported; 1 in the last 90 days worth $3.1M. Latest: Brennan David R filed on 2026-09-10 to sell 25,000 shares ($3.1M) from 2026-09-09.
| Filed | Seller | Shares | Market value | Of outstanding | Sale from | Broker |
|---|---|---|---|---|---|---|
| 2026-09-10 | Brennan David RDirector | 25K | $3.1M | 0.011% | 2026-09-09 | Wells Fargo Clearing Services |
| 2026-04-06 | William LewisOfficer | 11K | $1.7M | 0.005% | 2026-04-06 | Merrill Lynch |
| 2026-04-01 | Roger AdsettOfficer | 88K | $14.5M | 0.041% | 2026-04-01 | Merrill Lynch |
| 2026-03-30 | Michael SmithOfficer | 20K | $3.0M | 0.009% | 2026-03-30 | Merrill Lynch |
| 2026-03-19 | William LewisOfficer | 11K | $1.5M | 0.005% | 2026-03-19 | Merrill Lynch |
| 2026-03-05 | William LewisOfficer | 11K | $1.6M | 0.005% | 2026-03-05 | Merrill Lynch |
| 2026-02-24 | Michael SmithOfficer | 25K | $3.9M | 0.011% | 2026-02-24 | Merrill Lynch |
| 2026-02-19 | William LewisOfficer | 11K | $1.6M | 0.005% | 2026-02-19 | Merrill Lynch |
| 2026-02-09 | William LewisOfficer | 13K | $2.0M | 0.006% | 2026-02-09 | Merrill Lynch |
| 2026-02-05 | Martina FlammerOfficer | 869 | $132K | 0.000% | 2026-02-05 | Merrill Lynch |
| 2026-02-03 | Michael SmithOfficer | 640 | $100K | 0.000% | 2026-02-03 | Merrill Lynch |
| 2026-02-03 | William LewisOfficer | 3K | $470K | 0.001% | 2026-02-03 | Merrill Lynch |
| 2026-02-03 | Martina FlammerOfficer | 795 | $124K | 0.000% | 2026-02-03 | Merrill Lynch |
| 2026-02-03 | Sara BonsteinOfficer | 748 | $117K | 0.000% | 2026-02-03 | Merrill Lynch |
| 2026-02-03 | Roger AdsettOfficer | 791 | $124K | 0.000% | 2026-02-03 | Merrill Lynch |
| 2026-02-02 | Martina FlammerOfficer | 8K | $1.2M | 0.004% | 2026-02-02 | Merrill Lynch |
| 2026-01-20 | William LewisOfficer | 11K | $1.7M | 0.005% | 2026-01-20 | Merrill Lynch |
| 2026-01-12 | William LewisOfficer | 19K | $3.2M | 0.009% | 2026-01-12 | Merrill Lynch |
| 2026-01-08 | Michael SmithOfficer | 1K | $183K | 0.000% | 2026-01-08 | Merrill Lynch |
| 2026-01-08 | William LewisOfficer | 3K | $561K | 0.002% | 2026-01-08 | Merrill Lynch |
| 2026-01-08 | Martina FlammerOfficer | 5K | $895K | 0.002% | 2026-01-08 | Merrill Lynch |
| 2026-01-08 | Martina FlammerOfficer | 2K | $289K | 0.001% | 2026-01-08 | Merrill Lynch |
| 2026-01-08 | Sara BonsteinOfficer | 1K | $252K | 0.001% | 2026-01-08 | Merrill Lynch |
| 2026-01-08 | Roger AdsettOfficer | 2K | $359K | 0.001% | 2026-01-08 | Merrill Lynch |
| 2026-01-07 | Michael SmithOfficer | 709 | $124K | 0.000% | 2026-01-07 | Merrill Lynch |
| 2026-01-07 | William LewisOfficer | 2K | $413K | 0.001% | 2026-01-07 | Merrill Lynch |
| 2026-01-07 | Martina FlammerOfficer | 1K | $252K | 0.001% | 2026-01-07 | Merrill Lynch |
| 2026-01-07 | Sara BonsteinOfficer | 2K | $294K | 0.001% | 2026-01-07 | Merrill Lynch |
| 2026-01-07 | Roger AdsettOfficer | 802 | $140K | 0.000% | 2026-01-07 | Merrill Lynch |
| 2026-01-06 | Michael SmithOfficer | 1K | $242K | 0.001% | 2026-01-06 | Merrill Lynch |
| 2026-01-06 | William LewisOfficer | 4K | $710K | 0.002% | 2026-01-06 | Merrill Lynch |
| 2026-01-06 | Martina FlammerOfficer | 2K | $280K | 0.001% | 2026-01-06 | Merrill Lynch |
| 2026-01-06 | Sara BonsteinOfficer | 2K | $263K | 0.001% | 2026-01-06 | Merrill Lynch |
| 2026-01-06 | Roger AdsettOfficer | 1K | $248K | 0.001% | 2026-01-06 | Merrill Lynch |
| 2026-01-05 | Martina FlammerOfficer | 21K | $3.6M | 0.010% | 2026-01-05 | Merrill Lynch |
| 2026-01-02 | Stacey Nicole Schaeffer OrlovOfficer | 87K | $15.3M | 0.041% | 2026-01-02 | Merrill Lynch |
| 2025-12-18 | William LewisOfficer | 11K | $1.8M | 0.005% | 2025-12-18 | Merrill Lynch |
| 2025-12-05 | MELVIN SHAROKYDIRECTOR | 20K | $4.1M | 0.009% | 2025-12-05 | MERRILL LYNCH |
| 2025-12-04 | William LewisOfficer | 11K | $2.2M | 0.005% | 2025-12-04 | Merrill Lynch |
| 2025-12-01 | Martina FlammerOfficer | 9K | $1.8M | 0.004% | 2025-12-01 | Merrill Lynch |
| 2025-11-24 | ANDERSON ELIZABETH MDirector | 5K | $1.0M | 0.002% | 2025-11-24 | Fidelity Brokerage Services LLC |
| 2025-11-17 | Leo LeeDirector | 75K | $14.5M | 0.035% | 2025-11-17 | J.P. Morgan Securities LLC |
| 2025-11-13 | ANDERSON ELIZABETH MDirector | 10K | $1.9M | 0.005% | 2025-11-13 | FIDELITY BROKERAGE SERVICES LLC |
| 2025-11-12 | Stacey Nicole Schaeffer OrlovOfficer | 30K | $5.8M | 0.014% | 2025-11-12 | Merrill Lynch |
| 2025-11-12 | Martina FlammerOfficer | 31K | $5.9M | 0.015% | 2025-11-11 | Merrill Lynch |
| 2025-11-03 | Michael A SmithOfficer | 27K | $5.0M | 0.013% | 2025-11-03 | Merrill Lynch |
Large holders (13D and 13G)
One row per reporting person with its latest filing, newest first. JSON4 holders report 5% or more of INSM in their latest filing, all on Schedule 13G (passive). The largest reported stake is Abigail P. Johnson at 7.4% of the class (16,127,583 shares), filed 2026-08-06 for an event on 2026-06-30.
| Filed | Form | Holder | Shares | Of class | Event |
|---|---|---|---|---|---|
| 2026-08-14 | 13G/Ano. 5 | Dr. Abhishek Trehanindividual | 6.4M | 3.0% | 2026-06-30 |
| 2026-08-14 | 13G/Ano. 5 | Darwin Global Management, Ltd.investment adviser, other entity | 6.4M | 3.0% | 2026-06-30 |
| 2026-08-14 | 13G/Ano. 5 | Darwin Global Master Fund, Ltd.other entity | 6.3M | 2.9% | 2026-06-30 |
| 2026-08-06 | 13G/Ano. 1 | Abigail P. Johnsonindividual | 16.1M | 7.4% | 2026-06-30 |
| 2026-08-06 | 13G/Ano. 1 | FMR LLCparent holding company | 16.1M | 7.4% | 2026-06-30 |
| 2026-07-22 | 13G/Ano. 2 | JPMORGAN CHASE & CO.parent holding company | 10.4M | 4.7% | 2026-06-30 |
| 2026-04-30 | 13G | Vanguard Capital Managementinvestment adviser | 11.5M | 5.3% | 2026-03-31 |
| 2026-03-27 | 13G/Ano. 11 | The Vanguard Groupinvestment adviser | 0 | 0.0% | 2026-03-13 |
| 2026-01-21 | 13G/Ano. 13 | BlackRock, Inc.parent holding company | 14.1M | 6.6% | 2025-12-31 |
| 2025-11-14 | 13G/Ano. 15 | T. Rowe Price Associates, Inc.investment adviser | 6.9M | 3.3% | 2025-09-30 |
13F holders
Tracked managers holding INSM at their latest 13F. JSON8 of the 30 tracked managers held INSM at their latest 13F, $1.57B in total at quarter-end prices. D. E. Shaw & Co. is the largest at $626.7M (0.3% of its portfolio) as of 2026-06-30. Over the prior quarter 7 added shares and 1 cut.
| Fund | Quarter | Shares | Value | Of portfolio | Change in shares |
|---|---|---|---|---|---|
| D. E. Shaw & Co. | 2026-06-30 | 5.9M | $626.7M | 0.30% | +252K |
| Citadel Advisors | 2026-06-30 | 2.6M | $272.6M | 0.03% | +374K |
| Millennium Management | 2026-06-30 | 2.0M | $218.4M | 0.08% | +890K |
| Duquesne Family Office | 2026-06-30 | 1.4M | $151.9M | 2.92% | +271K |
| Two Sigma Investments | 2026-06-30 | 1.2M | $132.4M | 0.10% | +1.0M |
| AQR Capital Management | 2026-06-30 | 613K | $65.3M | 0.02% | -63K |
| Point72 Asset Management | 2026-06-30 | 537K | $57.3M | 0.06% | new |
| Bridgewater Associates | 2026-06-30 | 455K | $48.6M | 0.20% | +160K |
Only the 30 tracked managers on the funds hub; a 13F reports long positions in US listed stock at quarter end, 45 days late, and says nothing about shorts or positions sold since.
Financials
SEC XBRL, as filed. JSONIn Q2 FY 2026 (quarter ended 2026-06-30) Insmed reported revenue of $425.5M, up 296.1% from the same quarter a year earlier, and net loss of $13.2M (-0.06 diluted EPS). In FY 2025 it generated -$935.0M of operating cash flow. As of 2026-06-30, cash was $544.8M against $546.8M of debt.
- Cash
- $544.8M
- Debt
- $546.8M
- Equity
- $757.5M
- Total assets
- $2.10B
- Shares outstanding
- 218,381,503
Quarterly, last 8 quarters
| Quarter | Period end | Revenue | Net income | Margin | Diluted EPS |
|---|---|---|---|---|---|
| Q2 FY 2026 | 2026-06-30 | $425.5M | -$13.2M | -3.1% | -0.06 |
| Q1 FY 2026 | 2026-03-31 | $306.0M | -$163.6M | -53.5% | -0.76 |
| Q4 FY 2025derived | 2025-12-31 | $263.8M | -$328.5M | -124.5% | n/a |
| Q3 FY 2025 | 2025-09-30 | $142.3M | -$370.0M | -260.0% | -1.75 |
| Q2 FY 2025 | 2025-06-30 | $107.4M | -$321.7M | -299.5% | -1.70 |
| Q1 FY 2025 | 2025-03-31 | $92.8M | -$256.6M | -276.4% | -1.42 |
| Q4 FY 2024derived | 2024-12-31 | $104.4M | -$235.5M | -225.5% | n/a |
| Q3 FY 2024 | 2024-09-30 | $93.4M | -$220.5M | -236.0% | -1.27 |
Fiscal years, with buybacks and dividends
| Fiscal year | Ends | Revenue | Net income | Operating cash flow | Capex | Buybacks | Dividends |
|---|---|---|---|---|---|---|---|
| FY 2025 | 2025-12-31 | $606.4M | -$1.28B | -$935.0M | $32.6M | n/a | n/a |
| FY 2024 | 2024-12-31 | $363.7M | -$913.8M | -$683.9M | $21.9M | n/a | n/a |
| FY 2023 | 2023-12-31 | $305.2M | -$749.6M | -$536.2M | $13.3M | n/a | n/a |
| FY 2022 | 2022-12-31 | $245.4M | -$481.5M | -$400.4M | $9.9M | n/a | n/a |
| FY 2021 | 2021-12-31 | $188.5M | -$434.7M | -$363.3M | $7.3M | n/a | n/a |
Quarters are the three-month figures the company reports; a fourth quarter marked derived is the fiscal year less the three reported quarters, since companies report it only inside the 10-K. Fiscal years are the annual figures. Buybacks are the cash the company paid to repurchase its common stock in the year, not the amount authorized. Balance sheet lines are as of 2026-06-30; shares outstanding as of 2026-07-31 from the cover page.
What this page is
Insmed in the regulatory record
Regulators publish company data in separate files that never sit next to each other: FINRA's twice-monthly short interest, its daily short sale volume, the SEC's fails-to-deliver counts, and each insider's Form 4. A company page puts those series for one ticker on one URL, with planned sales, large holders, 13F holders and financials beside them, so the short position, the daily flow, the settlement fails and what insiders are doing can be read together.
Each section has its own history table, a one-line summary of the latest figures and its own JSON and CSV links, and says when its source last updated.
This page follows Insmed (INSM), SEC CIK 1104506, listed on Nasdaq, classified by the SEC as pharmaceutical preparations. The cross-market tables live on the short interest and insider transactions hubs.
Source and updates
- Short interest
- FINRA consolidated short interestSource: FINRA.Twice a month, about eight business days after settlement. Latest 2026-10-15.JSON and CSV
- Daily short volume
- FINRA Reg SHO daily filesSource: FINRA.Every trading day, the morning after FINRA posts it. Latest 2026-10-28.JSON and CSV
- Fails to deliver
- SEC fails-to-deliver dataSource: SEC.Twice a month, a few weeks after the half month ends. Latest 2026-09-25.JSON and CSV
- Planned sales
- SEC EDGAR Form 144Source: SEC.New notices appear shortly after the SEC posts them; a notice is filed on or before the sale. Latest 2026-09-10.JSON and CSV
- Large holders
- SEC EDGAR Schedule 13D and 13GSource: SEC.New filings appear shortly after the SEC posts them. A 13D is due within five business days of crossing 5%; a 13G follows the passive schedule. Latest 2026-08-14.JSON and CSV
- 13F holders
- SEC EDGAR Form 13F-HRSource: SEC.Quarterly, filed within 45 days of quarter end; 30 tracked managers. Latest 2026-06-30.JSON and CSV
- Financials
- SEC EDGAR 10-K and 10-Q filingsSource: SEC.Weekly; values are as filed in the 10-Q and 10-K. Latest 2026-06-30.JSON and CSV
- Earnings dates
- SEC EDGAR 8-K filings (Item 2.02)Source: SEC.Twice a day. Reported dates come from the company's 8-K filings; the next date is marked as an estimate until the 8-K arrives. Latest 2026-08-06.JSON and CSV
- Insider trades
- SEC EDGAR Form 4Source: SEC.New filings appear shortly after the SEC posts them; they're due two business days after the trade. Latest 2026-10-19.JSON and CSV
- Company record
- EDGAR filing index for CIK 1104506Ticker, name and exchange from the SEC's company list, refreshed weekly.
- Rate limits
- 10 requests a minute without a key, 30 with a free key from a free account.
How to read it
- Read the position against the flow: rising short interest with a high daily short share is new shorting; rising short interest with a normal short share is old shorts holding on.
- Insider buys next to a large short position are rare and stand out; insider sells next to one are common and mean little.
- Fails to deliver matter relative to the float, not in absolute shares; a million failed shares in a mega cap is noise.
Analysis of what the data shows, not advice. XOOMAR does not recommend buying, selling or holding anything.
Other companies the SEC classifies as pharmaceutical preparations
Other company pages
Datasets
Frequently Asked Questions
How much of INSM is sold short?
13,477,593 shares were held short at the 2026-10-15 settlement, 4.1 days of average volume. FINRA publishes the next count about eight business days after the 15th and the last business day of the month.
What is INSM's daily short volume?
On 2026-10-28, 993,801 of the 2,078,691 INSM shares reported to FINRA were sold short, 47.8% of the day's reported volume. Short volume is a flow for one day, not a position.
Does INSM have fails to deliver?
The SEC's latest file shows 30 INSM shares failed to deliver at settlement 2026-09-25. Fails are reported per settlement date and published twice a month with a lag.
Are INSM insiders buying or selling?
Insiders at INSM reported 5 open-market sells worth $39.2M in the last 90 days and no open-market buys. Latest filing: Hudson Paul (Director) on 2026-10-19.
Have INSM insiders filed to sell?
46 Form 144 notices on file for INSM worth $108.6M at the prices reported; 1 in the last 90 days worth $3.1M. Latest: Brennan David R filed on 2026-09-10 to sell 25,000 shares ($3.1M) from 2026-09-09.
Who owns 5% or more of INSM?
4 holders report 5% or more of INSM in their latest filing, all on Schedule 13G (passive). The largest reported stake is Abigail P. Johnson at 7.4% of the class (16,127,583 shares), filed 2026-08-06 for an event on 2026-06-30.
What did INSM report last quarter?
In Q2 FY 2026 (quarter ended 2026-06-30) Insmed reported revenue of $425.5M, up 296.1% from the same quarter a year earlier, and net loss of $13.2M (-0.06 diluted EPS). In FY 2025 it generated -$935.0M of operating cash flow. As of 2026-06-30, cash was $544.8M against $546.8M of debt.
Which tracked 13F managers own INSM?
8 of the 30 tracked 13F managers held INSM shares at their latest filing, $1.57B in all. The largest: D. E. Shaw & Co. (5.9M shares, $626.7M), Ken Griffin's Citadel Advisors (2.6M shares, $272.6M), Izzy Englander's Millennium Management (2.0M shares, $218.4M), Stanley Druckenmiller's Duquesne Family Office (1.4M shares, $151.9M), Two Sigma Investments (1.2M shares, $132.4M), Cliff Asness's AQR Capital Management (613K shares, $65.3M). The table above lists all 8.
Data on this page is provided for informational purposes only and is not financial advice. See our editorial policy.