Skip to main content
INSM logo

INSM · INSMED Inc

Track INSM — free
$118.54 -2.85 (-2.35%) At close · Aug 28
Market Cap
$26.51B
Shares
218.38M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 668
Total Value: $24,724,928,311
Total Shares: 231,947,616
Showing 1–100 of 714 holdings by value · page 1 of 8

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 668 13F filers · Δ vs Mar 31, 2026
Top Holder
7.0%
Sep 2023 → Jun 2026 · range 7.0% – 11.0%
−4.0 pts
Top 5
27.0%
Sep 2023 → Jun 2026 · range 27.0% – 41.0%
−9.9 pts
Top 10
42.4%
Sep 2023 → Jun 2026 · range 40.1% – 53.4%
−10.4 pts
HHI
255
Sep 2023 → Jun 2026 · range 255 – 424
Broadly held−128

Quarterly Activity

vs Mar 31, 2026
New
114
Increased
252
Decreased
233
Sold Out
126
Unchanged
69
Holder count: -12
Institutional value: -31.2%
Shares held: +5.5%

Top Buyers

vs Mar 31, 2026
Institution Added Now Holds Open

Top Sellers

vs Mar 31, 2026
Institution Sold Now Holds Open

Top New Positions

vs Mar 31, 2026
Institution Acquired Value (USD) Open

Top Sold-Out Positions

vs Mar 31, 2026
Institution Previously Held Last Value (USD) Open
Showing 100 of 714
Export CSV
Holder Value (USD) % of 13F Shares Open
Key facts CIK 1104506 CUSIP 457669307 13F (30d) 505 filings 502 filers Visit website Investor relations