Disc Medicine, Inc. (IRON) Ownership
IRON ownership summary
as of October 18, 2026- Institutions
- 116.0% of shares outstanding
- Insiders
- 7.84% of shares outstanding
- Shares outstanding
- 38.4M
- Float
- 32.9M shares available to trade
- Short interest
- 22.08% 7.3M shares short
- Days to cover
- 12.69 short interest up 0.9% vs prior month
- Institutions 115.95%
- Insiders 7.84%
IRON top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | FMR Inc | 12.75% | 4.9M | $278.2M | −692,421 (−12.4%) | June 30, 2026 |
| 2 | BlackRock Inc | 6.43% | 2.5M | $140.3M | +194,068 (+8.5%) | June 30, 2026 |
| 3 | RA Capital Management, LLC | 6.38% | 2.5M | $139.3M | — | June 30, 2026 |
| 4 | JPMorgan Chase & Co | 4.89% | 1.9M | $106.6M | +504,315 (+36.8%) | June 30, 2026 |
| 5 | T. Rowe Price Associates, Inc. | 4.88% | 1.9M | $106.6M | +326,049 (+21.0%) | June 30, 2026 |
| 6 | Wellington Management Company LLP | 4.54% | 1.7M | $99.0M | +5,975 (+0.3%) | June 30, 2026 |
| 7 | State Street Corp | 4.29% | 1.6M | $93.7M | −49,408 (−2.9%) | June 30, 2026 |
| 8 | Vestal Point Capital LP | 4.04% | 1.6M | $88.1M | +850,000 (+121.4%) | June 30, 2026 |
| 9 | Atlas Venture Life Science Advisors, LLC | 3.94% | 1.5M | $86.0M | — | June 30, 2026 |
| 10 | Vanguard Capital Management, LLC | 3.57% | 1.4M | $77.8M | −6,403 (−0.5%) | June 30, 2026 |
| 11 | Frazier Life Sciences Management, L.P. | 3.53% | 1.4M | $77.0M | — | June 30, 2026 |
| 12 | TCG Crossover Management, LLC | 3.50% | 1.3M | $76.3M | — | June 30, 2026 |
| 13 | Bvf Inc | 3.00% | 1.2M | $65.6M | −118,700 (−9.3%) | June 30, 2026 |
| 14 | Woodline Partners LP | 2.50% | 958K | $54.5M | — | June 30, 2026 |
| 15 | Siren, L.L.C. | 2.31% | 888K | $50.5M | −100,000 (−10.1%) | June 30, 2026 |
| 16 | Logos Global Management LP | 2.28% | 875K | $49.7M | +315,000 (+56.2%) | June 30, 2026 |
| 17 | Opaleye Management Inc | 2.23% | 855K | $48.6M | +434,000 (+103.1%) | June 30, 2026 |
| 18 | Geode Capital Management, LLC | 2.06% | 790K | $44.9M | +45,502 (+6.1%) | June 30, 2026 |
| 19 | Assenagon Asset Management SA | 2.00% | 768K | $43.7M | +222,069 (+40.7%) | June 30, 2026 |
| 20 | Deerfield Management Co | 1.71% | 657K | $37.3M | — | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 9 holders added 2.9M shares and 5 cut 967K.
IRON top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Strategic Advisers Fidelity US TtlStk | 5.60% | 2.2M | $122.3M | +241,648 (+12.7%) | August 31, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 2.54% | 975K | $55.4M | −2,171 (−0.2%) | August 31, 2026 |
| 3 | iShares Russell 2000 ETF | 1.91% | 733K | $41.6M | −8,448 (−1.1%) | September 30, 2026 |
| 4 | State Street® SPDR® S&P® Biotech ETF | 1.89% | 724K | $41.2M | −13,850 (−1.9%) | September 30, 2026 |
| 5 | JPMorgan Mid Cap Growth I | 1.72% | 661K | $37.6M | −167,919 (−20.3%) | August 31, 2026 |
| 6 | T. Rowe Price New Horizons | 1.20% | 459K | $26.1M | −56,915 (−11.0%) | September 30, 2026 |
| 7 | Fidelity Select Biotechnology | 1.18% | 455K | $25.8M | — | August 31, 2026 |
| 8 | Eventide Healthcare & Life Sciences I | 1.03% | 395K | $22.5M | — | June 30, 2026 |
| 9 | Fidelity Select Health Care | 0.99% | 380K | $21.6M | −20,000 (−5.0%) | August 31, 2026 |
| 10 | T. Rowe Price Integrated US Sm Gr Eq | 0.98% | 376K | $21.3M | — | September 30, 2026 |
| 11 | JPMorgan Small Cap Growth A | 0.83% | 319K | $18.1M | −9,414 (−2.9%) | August 31, 2026 |
| 12 | Fidelity Small Cap Index | 0.81% | 309K | $17.6M | +2,432 (+0.8%) | July 31, 2026 |
| 13 | Fidelity Small Cap Growth | 0.73% | 278K | $15.8M | — | July 31, 2026 |
| 14 | iShares Russell 2000 Growth ETF | 0.69% | 265K | $15.1M | −335 (−0.1%) | September 30, 2026 |
| 15 | Pictet-Biotech P USD | 0.65% | 250K | $14.2M | −1,015 (−0.4%) | June 30, 2026 |
| 16 | Loomis Sayles Small Cap Growth Instl | 0.65% | 248K | $14.1M | +16,785 (+7.3%) | August 31, 2026 |
| 17 | MEDICAL BioHealth EUR Acc | 0.63% | 242K | $13.8M | +51 (+0.0%) | August 31, 2026 |
| 18 | Fidelity Stock Selector Small Cap | 0.58% | 222K | $12.6M | — | July 31, 2026 |
| 19 | iShares Biotechnology ETF | 0.58% | 221K | $12.6M | −1,672 (−0.8%) | September 30, 2026 |
| 20 | Fidelity VIP Mid Cap Initial | 0.54% | 209K | $11.9M | — | August 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
IRON insider transactions
latest 20| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-14 | Jean M Franchi | Sell | $69.24 | 6,257 | $433,235 |
| 2026-04-13 | William Jacob Savage | Sell | $66.38 | 5,731 | $380,424 |
| 2026-04-13 | Jean M Franchi | Sell | $69.00 | 400 | $27,600 |
| 2026-03-02 | William Jacob Savage | Sell | $65.88 | 7,378 | $486,063 |
| 2026-02-25 | Jean M Franchi | Sell | $69.06 | 353 | $24,378 |
| 2026-02-18 | Jean M Franchi | Sell | $65.47 | 7,081 | $463,593 |
| 2026-02-17 | Rahul Khara | Sell | $62.86 | 2,853 | $179,340 |
| 2026-02-17 | William Jacob Savage | Sell | $62.86 | 3,256 | $204,672 |
| 2026-02-17 | Pamela Stephenson | Sell | $62.86 | 5,531 | $347,679 |
| 2026-02-17 | Jonathan Yen-Wen Yu | Sell | $62.86 | 3,231 | $203,101 |
| 2026-02-17 | John D Quisel | Sell | $62.86 | 13,264 | $833,775 |
| 2026-02-17 | Jean M Franchi | Sell | $62.86 | 4,075 | $256,154 |
| 2026-01-20 | Rahul Khara | Sell | $69.74 | 1,000 | $69,740 |
| 2026-01-02 | Rahul Khara | Sell | $78.69 | 6,500 | $511,485 |
| 2025-12-17 | Kevin Bitterman | Sell | $91.47 | 754 | $68,968 |
| 2025-12-16 | Kevin Bitterman | Sell | $91.24 | 68,923 | $6.3M |
| 2025-12-15 | Kevin Bitterman | Sell | $91.28 | 62,693 | $5.7M |
| 2025-12-15 | William Jacob Savage | Sell | $91.22 | 13,093 | $1.2M |
| 2025-12-15 | Kevin Bitterman | Sell | $91.87 | 7,000 | $643,090 |
| 2025-12-12 | Kevin Bitterman | Sell | $92.39 | 45,507 | $4.2M |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
IRON shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns IRON
Institutional investors own 116.0% of Disc Medicine's shares and insiders 7.84%. The largest holder is FMR Inc with 12.75% of the shares (4.9M), as of June 30, 2026. Among the top 20 institutions, 9 added shares and 5 reduced their stake in the latest filings. Short interest is 22.08% of the float, or 12.69 days of average trading volume. The share count rose 2,172.0% since 2020.
Related: IRON analyst forecast, IRON key metrics. See the IRON stock overview for the latest quote and news.
IRON ownership FAQ
Who owns the most Disc Medicine stock?
The largest shareholders of Disc Medicine are FMR Inc (12.75%), BlackRock Inc (6.43%), RA Capital Management, LLC (6.38%), JPMorgan Chase & Co (4.89%), T. Rowe Price Associates, Inc. (4.88%).
What percentage of Disc Medicine is owned by institutions?
Institutions hold 116.0% of Disc Medicine's shares outstanding; insiders hold 7.84%.
Which funds own Disc Medicine?
The largest fund holders of Disc Medicine are Strategic Advisers Fidelity US TtlStk (5.60%), Vanguard MStar Total Stk Mkt Idx Invest (2.54%), iShares Russell 2000 ETF (1.91%), State Street® SPDR® S&P® Biotech ETF (1.89%), JPMorgan Mid Cap Growth I (1.72%).
What is Disc Medicine's short interest?
7.3M shares of Disc Medicine were sold short, 22.08% of the float; at the average daily volume it would take 12.69 days to cover.
Are insiders buying or selling Disc Medicine?
Of the latest 20 reported insider transactions in Disc Medicine (since December 12, 2025), 0 were purchases and 20 were sales.
How many shares of Disc Medicine are outstanding?
Disc Medicine has 38.4M shares outstanding, of which 32.9M are in the public float.