INSM — INSMED INC
Public company
InvestorLens aggregates public filing data to show which tracked investors reported holdings in this stock. Dollar values represent reported position values, not market capitalization, and may be delayed up to 45 days. Not a recommendation.
Sourced from SEC EDGAR public filings
Why are billionaires buying INSM?
Built from public SEC filings and public economic data. Not a recommendation.
Why? — Evidence & Confidence ▾
Of 3 tracked investors who changed their INSM position last quarter, 3 bought and 0 sold (100% buy-side). Macro conditions are mixed for this sector (Macro Tailwind 56/100 in a Overheat regime). 0 congressional purchases, 1 sale disclosed in the last 6 months.
- +3 tracked investors added or increased positions last quarter (Ray Dalio, Paul Tudor Jones, Stanley Druckenmiller)
- +6 tracked investors reported holding INSM at their latest filing
- +Macro Health is 56/100 in a Overheat regime — historically acceptable for this sectorsource
- −Congressional disclosures lean toward selling (1 sales vs 0 purchases, 6 months)
- −13F data is disclosed up to 45 days after quarter end — positions may have changed since
- · 13F disclosure lag (up to 45 days)
- · Tracked investors are a sample, not the whole market
- · Sector regime fit is a historical average, not a guarantee
Every InvestorLens score shows its evidence — including what argues against it. Model conviction-v1 · generated 9/18/2026.
About INSMED INC (INSM)
INSMED INC (INSM) appears in the most recent 13F filings of 6 tracked institutional investors. The largest disclosed position is held by Ken Griffin (Citadel Advisors), valued at $427M. Across recent filings, tracked investors recorded 7 new positions, 8 increased, 11 reduced, and 4 exited. All data sourced from SEC 13F filings.
Based on recent institutional activity in INSM
How many top investors track INSM
Several tracked investors have exposure.
INSM Ownership Composition
How INSMED INC is held across tracked investor types, based on reported 13F positions.
- Multi-Strategy / Quant64.0%
- Macro36.0%
Tracked investors currently reporting INSM
2 tracked investors have since exited this position — listed separately below.
- Ken GriffinJun 30, 2026Citadel AdvisorsShares3.2MValue$339.9M% Portfolio0.04%
- Stanley DruckenmillerJun 30, 2026Duquesne Family OfficeShares2.8MValue$295.8M% Portfolio5.68%
- Izzy EnglanderJun 30, 2026Millennium ManagementShares2.9MValue$312.2M% Portfolio0.11%
- Steve CohenJun 30, 2026Point72 Asset ManagementShares539.1KValue$57.5M% Portfolio0.06%
- Paul Tudor JonesJun 30, 2026Tudor Investment CorpShares513.6KValue$54.8M% Portfolio0.08%
- Ray DalioJun 30, 2026Bridgewater AssociatesShares455.4KValue$48.6M% Portfolio0.20%
Previously held INSM
These investors reported INSM in an earlier quarter but not in their most recent 13F. Figures below are their last reported position, not a current holding.
| Investor | Firm | Last reported shares | Value then | Last held |
|---|---|---|---|---|
| George Soros | Soros Fund Management | 307.2K | $23.4M | Mar 31, 2025 |
| Howard Marks | Oaktree Capital Management | 1.6M | $3.6M | Dec 31, 2024 |
Recent activity
- Reduced$31.4M(-4.91%)Feb 14, 2025
- Reduced$23.4M(-32.49%)May 15, 2025
- Sold$0(-100.00%)Aug 14, 2025
- Reduced$3.5M(-17.61%)Aug 14, 2024
- Unchanged$3.8M(0.00%)Nov 14, 2024
- Unchanged$3.6M(0.00%)Feb 12, 2025
- Sold$0(-100.00%)May 15, 2025
- New$48.3MMay 15, 2026
- Increased$48.6M(54.07%)Aug 14, 2026
- Reduced$23M(-93.70%)Nov 14, 2024
- Sold$0(-100.00%)Feb 14, 2025
- New$49.4MAug 14, 2025
- Reduced$66.9M(-5.39%)Nov 14, 2025
- Sold$0(-100.00%)Feb 17, 2026
- $2.7MNov 14, 2024
- Reduced$2.1M(-16.09%)Feb 14, 2025
- Reduced$1.2M(-49.51%)May 15, 2025
- Increased$15.4M(884.58%)Aug 14, 2025
- Reduced$14.8M(-32.44%)Dec 9, 2025
- Reduced$5.2M(-71.29%)May 15, 2026
- Increased$54.8M(1510.00%)Aug 14, 2026
- $1.3MAug 14, 2024
- Unchanged$1.5M(0.00%)Nov 14, 2024
- Increased$41M(2867.35%)Feb 14, 2025
- Increased$104.4M(130.69%)May 15, 2025
- Increased$236.9M(71.90%)Aug 15, 2025
- Increased$349M(2.97%)Nov 14, 2025
- Reduced$257.9M(-38.86%)Feb 17, 2026
- Reduced$188.7M(-22.11%)May 15, 2026
- Increased$295.8M(140.42%)Aug 14, 2026
- New$10.6MSep 16, 2024
- New$2.1MMay 14, 2024
- New$34.9MNov 14, 2024
Frequently asked questions
- How many institutional investors hold INSM?
- 6 tracked institutional investors disclosed a position in INSM (INSMED INC) in their most recent 13F filing.
- Who is the largest institutional holder of INSM?
- Ken Griffin, Citadel Advisors, holds the largest disclosed position in INSM, valued at $427M.
- Did institutional ownership of INSM increase or decrease?
- Across recent 13F filings, tracked investors recorded 7 new positions, 8 increased, 11 reduced, and 4 fully exited INSM.
- Where does this INSM ownership data come from?
- SEC Form 13F-HR filings, accessed via EDGAR. 13F filings are disclosed quarterly with a 45-day reporting delay and cover U.S.-listed long equity positions only. This is not investment advice.