Supply breakdown
Shares as of Oct 23, 2026| Category | Shares | % | Value | Status |
|---|---|---|---|---|
| Circulating | 219.38M | 100.0% | $23.39B | Estimated |
| Free float | - | - | - | Unavailable |
| Insider-held, unrestricted | - | - | - | Unavailable |
| Locked team funds | - | - | - | Unavailable |
| Other restricted (unlisted classes only) | - | - | - | Unavailable |
| Total outstanding | 219.38M | 100.0% | $23.39B | Verified |
| Ownership views (overlap the categories above, never added) | ||||
| Institutional holdings (13F; over 100%, double counted) | 223.63M | 101.9% | $23.84B | Estimated |
| Insider-held, all (Forms 3, 4, 5) | - | - | - | Unavailable |
Institutional and insider holdings can include both tradable and locked shares, so they are shown for reference and never added to the total. Check: no class has more shares deducted than it has outstanding, and the review found no shares that may be counted twice: reconciles.
Valuation
- Traditional$23.39B
- Fully diluted-
- Circulating$23.39B
- Free float-
- Locked team value$0
- Other restricted value$0
Locked and restricted shares
Not reviewed yet.
Institutional holders
13F, quarter ended Jun 30, 2026| Holder | Shares | % of total |
|---|---|---|
| FMR LLC | 16.14M | 7.36% |
| BlackRock, Inc. | 15.81M | 7.21% |
| JPMORGAN CHASE & CO | 10.43M | 4.75% |
| VANGUARD PORTFOLIO MANAGEMENT LLC | 10.41M | 4.74% |
| VANGUARD CAPITAL MANAGEMENT LLC | 9.79M | 4.46% |
| BAKER BROS. ADVISORS LP | 8.80M | 4.01% |
| Capital International Investors | 8.24M | 3.76% |
| Darwin Global Management, Ltd. | 6.43M | 2.93% |
| AMERIPRISE FINANCIAL INC | 6.18M | 2.82% |
| Orbis Allan Gray Ltd | 6.08M | 2.77% |
Sum of long share positions in Form 13F reports for the quarter. 13F covers managers with over $100M in US equities; some positions are reported by more than one filer. The total is 102% of shares outstanding, so it counts some shares twice: positions reported by more than one manager, and lent shares that appear at both the lender and the buyer. Read it as an upper bound.
Insiders
Forms 3, 4 and 5Form 4 aggregation pending
Share classes
| Class | Listing | Shares outstanding | As of |
|---|---|---|---|
| Common stock | INSM on Nasdaq | 219,380,309 | Oct 23, 2026 |
Notes and sources
- INSMED Inc 10-Q for period ended 2026-09-30, Cover page (0001104506-26-000047)
- SEC public float (non-affiliates): $21.10B as of Jun 30, 2025, from the 10-K cover. It is a dollar value at a past date, not circulating supply.