INSMED INC (INSM) Institutional Shareholders
INSMED INC (INSM) is currently reported in institutional portfolios tracked by InsiderSet based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026. The institutional investors covered on this page collectively reported approximately $22.54B in INSM holdings during the latest filing period.
Fmr Llc is currently the largest disclosed institutional shareholder of INSM tracked by InsiderSet, reporting ownership valued at approximately $1.72B in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $2.04B, representing an estimated gain of +18.49% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 46% of the total disclosed INSM value among the investors covered in this analysis. Major shareholders include Fmr Llc, Blackrock, Inc., Vanguard Portfolio Management Llc, and several other long-term asset managers with concentrated positions in INSMED INC (INSM).
This page ranks the largest institutional INSM shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
657
Total Reported Value
$22.54B
Largest Holder
Fmr Llc
Largest Position
$1.72B
Insider Transactions (90d)
41
Latest Filing Quarter
Q2 2026
New Institutional Positions
56
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Fmr Llc | 0.07% | 16,143,583 | $1,721,228,828 | $2,039,418,840 | +$318,190,012 | +18.49% | |
| Blackrock, Inc. | 0.03% | 15,807,984 | $1,685,447,191 | $1,997,022,619 | +$311,575,428 | +18.49% | |
| Vanguard Portfolio Management Llc | 0.05% | 10,407,962 | $1,109,696,908 | $1,314,837,839 | +$205,140,931 | +18.49% | |
| Jpmorgan Chase & Co | 0.06% | 10,428,170 | $1,092,246,620 | $1,317,390,716 | +$225,144,096 | +20.61% | |
| Vanguard Capital Management Llc | 0.02% | 9,790,865 | $1,043,902,026 | $1,236,879,975 | +$192,977,949 | +18.49% | |
| Baker Bros. Advisors Lp | 4.70% | 8,796,111 | $937,841,355 | $1,111,212,703 | +$173,371,348 | +18.49% | |
| Capital International Investors | 0.18% | 8,238,124 | $878,338,960 | $1,040,722,205 | +$162,383,245 | +18.49% | |
| Darwin Global Management, Ltd. | 17.91% | 6,431,163 | $673,600,013 | $812,448,822 | +$138,848,809 | +20.61% | |
| Ameriprise Financial Inc | 0.13% | 6,179,571 | $658,878,001 | $780,665,204 | +$121,787,203 | +18.48% | |
| Orbis Allan Gray Ltd | 2.23% | 6,076,487 | $647,875,044 | $767,642,603 | +$119,767,559 | +18.49% | |
| State Street Corp | 0.02% | 6,052,174 | $645,282,792 | $764,571,141 | +$119,288,349 | +18.49% | |
| D. E. Shaw & Co., Inc. | 0.39% | 5,877,959 | $626,707,989 | $742,562,560 | +$115,854,571 | +18.49% | |
| Artisan Partners Limited Partnership | 0.95% | 5,441,718 | $580,195,955 | $687,452,235 | +$107,256,280 | +18.49% | |
| Rtw Investments, Lp | 4.41% | 4,842,880 | $516,347,866 | $611,801,030 | +$95,453,164 | +18.49% | |
| Geode Capital Management, Llc | 0.02% | 4,220,155 | $448,763,113 | $533,132,181 | +$84,369,068 | +18.80% | |
| Norges Bank | 0.04% | 3,377,641 | $360,124,083 | $426,697,388 | +$66,573,305 | +18.49% | |
| Ubs Group Ag | 0.04% | 2,584,446 | $275,553,633 | $326,493,063 | +$50,939,430 | +18.49% | |
| Citadel Advisors Llc | 0.16% | 2,556,973 | $272,624,461 | $323,022,399 | +$50,397,938 | +18.49% | |
| Maverick Capital Ltd | 2.07% | 2,150,762 | $229,314,244 | $271,705,763 | +$42,391,519 | +18.49% | |
| Millennium Management Llc | 0.15% | 2,048,005 | $218,358,293 | $258,724,472 | +$40,366,179 | +18.49% | |
| Ubs Am, A Distinct Business Unit Of Ubs Asset Management Americas Llc | 0.04% | 1,215,025 | $198,680,888 | $153,494,108 | -$45,186,780 | -22.74% | |
| Qube Research & Technologies Ltd | 0.20% | 1,682,334 | $179,370,451 | $212,529,254 | +$33,158,803 | +18.49% | |
| Westfield Capital Management Co Lp | 0.57% | 1,629,561 | $173,743,795 | $205,862,441 | +$32,118,646 | +18.49% | |
| Integral Health Asset Management, Llc | 7.00% | 1,600,000 | $170,592,000 | $202,128,000 | +$31,536,000 | +18.49% | |
| Goldman Sachs Group Inc | 0.02% | 1,409,885 | $150,322,007 | $178,110,772 | +$27,788,765 | +18.49% | |
| Vanguard Fiduciary Trust Co | 0.03% | 1,401,552 | $149,433,474 | $177,058,064 | +$27,624,590 | +18.49% | |
| Bellevue Group Ag | 3.13% | 1,393,418 | $148,566,227 | $176,030,496 | +$27,464,269 | +18.49% | |
| Balyasny Asset Management L.P. | 0.26% | 1,326,430 | $141,423,967 | $167,567,902 | +$26,143,935 | +18.49% | |
| Paradigm Biocapital Advisors Lp | 2.65% | 1,325,977 | $141,375,668 | $167,510,674 | +$26,135,006 | +18.49% | |
| Northern Trust Corp | 0.02% | 1,315,325 | $140,239,951 | $166,165,007 | +$25,925,056 | +18.49% | |
| Bank Of New York Mellon Corp | 0.02% | 1,312,756 | $139,965,961 | $165,840,465 | +$25,874,504 | +18.49% | |
| Two Sigma Investments, Lp | 0.10% | 1,242,222 | $132,445,710 | $156,929,905 | +$24,484,195 | +18.49% | |
| Morgan Stanley | 0.01% | 1,233,498 | $131,515,791 | $155,827,802 | +$24,312,011 | +18.49% | |
| Pictet Asset Management Holding Sa | 0.12% | 1,220,353 | $129,804,038 | $154,167,194 | +$24,363,156 | +18.77% | |
| Charles Schwab Investment Management Inc | 0.02% | 1,213,963 | $129,432,735 | $153,359,946 | +$23,927,211 | +18.49% | |
| Sixth Street Partners Management Company, L.P. | 0.02% | 1,213,963 | $129,432,735 | $153,359,946 | +$23,927,211 | +18.49% | |
| Hood River Capital Management Llc | 0.82% | 1,056,871 | $112,683,586 | $133,514,513 | +$20,830,927 | +18.49% | |
| Bank Of America Corp | 0.01% | 1,023,114 | $109,084,466 | $129,249,992 | +$20,165,526 | +18.49% | |
| Sei Investments Co | 0.10% | 1,015,870 | $108,312,723 | $128,334,857 | +$20,022,134 | +18.49% | |
| Castle Hook Partners Lp | 1.13% | 993,310 | $105,906,712 | $125,484,852 | +$19,578,140 | +18.49% | |
| Jennison Associates Llc | 0.06% | 905,094 | $96,501,143 | $114,340,525 | +$17,839,382 | +18.49% | |
| Polar Capital Holdings Plc | 0.27% | 890,872 | $94,984,773 | $112,543,860 | +$17,559,087 | +18.49% | |
| Fil Ltd | 0.07% | 856,214 | $91,289,537 | $108,165,515 | +$16,875,978 | +18.49% | |
| Principal Financial Group Inc | 0.04% | 856,126 | $91,280,154 | $108,154,398 | +$16,874,244 | +18.49% | |
| Adage Capital Partners Gp, L.L.C. | 0.13% | 850,000 | $90,627,000 | $107,380,500 | +$16,753,500 | +18.49% | |
| Fiera Capital Corp | 0.33% | 843,042 | $89,885,138 | $106,501,496 | +$16,616,358 | +18.49% | |
| Legal & General Group Plc | 0.02% | 826,431 | $88,114,072 | $104,403,028 | +$16,288,956 | +18.49% | |
| Frontier Capital Management Co Llc | 0.79% | 795,242 | $84,788,663 | $100,462,922 | +$15,674,259 | +18.49% | |
| American Century Companies Inc | 0.04% | 759,735 | $81,002,980 | $95,977,323 | +$14,974,343 | +18.49% | |
| Samlyn Capital, Llc | 1.29% | 732,568 | $78,106,400 | $92,545,315 | +$14,438,915 | +18.49% |
Frequently asked questions about INSM
Who owns the most INSM stock?
The largest holders of INSM are typically major institutional investors such as asset managers and hedge funds reporting on Form 13F. The table above ranks tracked superinvestors by reported position size using the latest available filings for INSMED INC (INSM).
Is INSM widely held by superinvestors?
Many widely followed stocks like INSM appear across numerous superinvestor portfolios because of liquidity, index inclusion, and fundamentals. The holder count and table above show how broadly INSM is represented among the institutional managers we track.
What do “Current Estimated Value”, “Gain/loss Since Filing”, and “Estimated Portfolio Performance” mean?
Current Estimated Value is reported share quantity from the latest 13F times our most recent split-adjusted U.S. session close. Gain/loss Since Filing is that estimate minus the reported 13F dollar value; Estimated Portfolio Performance is that difference as a percent of the reported value. Green means the estimate is above the filing value; red means below (not purchase cost). If many filers share the same implied filing price per share, the performance % may match across rows. These are not official fund marks or live quotes.