DISC MEDICINE INC IRON
COM · Common Stock · CUSIP 254604101
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersWatertown, MA
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($503.1k this quarter). Holder counts are more reliable. Shares outstanding: 38.4m as of 2026-07-23, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $73.20. Options: 10 managers hold calls ($26.6m notional), 6 hold puts ($4.7m).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q4 2022 | 35 |
| Q1 2023 | 46 |
| Q2 2023 | 91 |
| Q3 2023 | 92 |
| Q4 2023 | 113 |
| Q1 2024 | 132 |
| Q2 2024 | 123 |
| Q3 2024 | 134 |
| Q4 2024 | 154 |
| Q1 2025 | 159 |
| Q2 2025 | 153 |
| Q3 2025 | 168 |
| Q4 2025 | 198 |
| Q1 2026 | 204 |
| Q2 2026 | 217 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 80 | 40 |
| Q4 2024 | 79 | 60 |
| Q1 2025 | 98 | 52 |
| Q2 2025 | 92 | 69 |
| Q3 2025 | 88 | 52 |
| Q4 2025 | 122 | 59 |
| Q1 2026 | 120 | 82 |
| Q2 2026 | 113 | 84 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $3.1m | $871.3k | 0.28 |
| Q4 2025 | $2.5m | $9.4m | 3.73 |
| Q1 2026 | $23.3m | $5.0m | 0.21 |
| Q2 2026 | $26.6m | $4.7m | 0.18 |
Biggest buyers
| Vestal Point Capital, LP | Added | +850.0k |
| JPMORGAN CHASE & CO | Added | +504.3k |
| Opaleye Management Inc. | Added | +434.0k |
| PRICE T ROWE ASSOCIATES INC /MD/ | Added | +326.0k |
| Logos Global Management LP | Added | +315.0k |
| Assenagon Asset Management S.A. | Added | +222.1k |
| BlackRock, Inc. | Added | +194.1k |
| DIMENSIONAL FUND ADVISORS LP | Added | +174.6k |
| TWO SIGMA INVESTMENTS, LP | New | +136.8k |
| CITADEL ADVISORS LLC | Added | +111.4k |
Biggest sellers
| ORBIMED ADVISORS LLC | Reduced | -710.0k |
| FMR LLC | Reduced | -692.4k |
| GOLDMAN SACHS GROUP INC | Reduced | -542.5k |
| JENNISON ASSOCIATES LLC | Reduced | -170.9k |
| Integral Health Asset Management, LLC | Sold out | -170.0k |
| BVF INC/IL | Reduced | -118.7k |
| SILVERARC CAPITAL MANAGEMENT, LLC | Reduced | -113.2k |
| Siren, L.L.C. | Reduced | -100.0k |
| ARMISTICE CAPITAL, LLC | Reduced | -76.0k |
| Ensign Peak Advisors, Inc | Reduced | -69.4k |
Biggest calls
| Caption Management, LLC | Reduced | $11.0m150.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $5.4m73.6k shares |
| PEAK6 LLC | New | $4.4m60.0k shares |
| Squadron Capital Management LLC | New | $2.2m30.0k shares |
| CITADEL ADVISORS LLC | Added | $1.2m15.8k shares |
| Ikarian Capital, LLC | New | $972.8k13.3k shares |
| JANE STREET GROUP, LLC | Added | $665.6k9.1k shares |
| SIMPLEX TRADING, LLC | Reduced | $438.8k6.0k shares |
| BOOTHBAY FUND MANAGEMENT, LLC | New | $292.6k4.0k shares |
| GROUP ONE TRADING LLC | New | $160.9k2.2k shares |
Biggest puts
| DLD Asset Management, LP | New | $1.3m18.2k shares |
| CITADEL ADVISORS LLC | Reduced | $1.3m17.2k shares |
| Ikarian Capital, LLC | New | $972.8k13.3k shares |
| JANE STREET GROUP, LLC | New | $526.6k7.2k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $365.7k5.0k shares |
| BOOTHBAY FUND MANAGEMENT, LLC | New | $292.6k4.0k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| FMR LLC 13G · institution -1.3 pts · filed 2026-08-06 | 12.8% |
| AI DMI LLC 13D · may seek influence -1.4 pts · filed 2026-10-26 | 6.6% |
| RA CAPITAL MANAGEMENT, L.P. 13G · passive investor new · filed 2026-01-07 | 5.9% |
Fell to 5% or below in the last year: Atlas Venture Fund X, L.P. (2.2%, 2025-12-17)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 3 | $4.9m | $4.9m |
| Q1 2025 | 0 | — | 8 | $21.9m | $887.2k |
| Q2 2025 | 0 | — | 2 | $693.8k | $693.8k |
| Q3 2025 | 0 | — | 3 | $7.8m | $5.1m |
| Q4 2025 | 0 | — | 4 | $38.7m | $7.5m |
| Q1 2026 | 0 | — | 6 | $3.6m | $1.8m |
| Q2 2026 | 0 | — | 5 | $6.0m | $6.0m |
| Q3 2026 | 0 | — | 4 | $12.7m | $10.8m |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-09-11 | Bitterman Kevin Director | Sold | $1.9m27.1k shares |
| 2026-09-04 | Bitterman Kevin Director · See footnote | Sold plan | $135.1k1.7k shares |
| 2026-09-03 | Bitterman Kevin Director · See footnote | Sold plan | $416.1k5.2k shares |
| 2026-09-02 | Bitterman Kevin Director · See footnote | Sold plan | $3.9m49.2k shares |
| 2026-09-01 | Bitterman Kevin Director · See footnote | Sold plan | $10.3k129 shares |
| 2026-08-25 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $731.1k8.8k shares |
| 2026-08-24 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $24.8k300 shares |
| 2026-08-17 | Quisel John D Chief Executive Officer, director | Sold plan | $2.6m33.0k shares |
| 2026-08-12 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $66.4k804 shares |
| 2026-08-06 | Khara Rahul Chief Legal Officer | Sold plan | $400.0k5.0k shares |
| 2026-07-13 | Quisel John D Chief Executive Officer, director | Sold plan | $2.5m33.0k shares |
| 2026-07-07 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $8.2k100 shares |
| 2026-06-29 | Khara Rahul Chief Legal Officer | Sold plan | $123.7k1.6k shares |
| 2026-06-26 | Khara Rahul Chief Legal Officer | Sold plan | $63.8k851 shares |
| 2026-06-26 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $21.8k300 shares |
| 2026-06-22 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $704.8k9.7k shares |
| 2026-06-18 | Quisel John D Chief Executive Officer, director | Sold plan | $2.4m34.0k shares |
| 2026-06-18 | Khara Rahul Chief Legal Officer | Sold plan | $526.7k7.5k shares |
| 2026-06-16 | Yu Jonathan Yen-Wen Chief Operating Officer | Sold plan | $1.3m18.6k shares |
| 2026-04-14 | Franchi Jean M. Chief Financial Officer | Sold plan | $433.2k6.3k shares |
| 2026-04-13 | Savage William Jacob Chief Medical Officer | Sold plan | $380.5k5.7k shares |
| 2026-04-13 | Franchi Jean M. Chief Financial Officer | Sold plan | $27.6k400 shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.02% of their portfolio | 4.9m $358.0m | Reduced -692.4k |
| BlackRock, Inc. 0.00% of their portfolio | 2.5m $180.5m | Added +194.1k |
| RA CAPITAL MANAGEMENT, L.P. 1.56% of their portfolio | 2.5m $179.2m | Unchanged |
| JPMORGAN CHASE & CO 0.01% of their portfolio | 1.9m $139.9m | Added +504.3k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.01% of their portfolio | 1.9m $137.2m | Added +326.0k |
| WELLINGTON MANAGEMENT GROUP LLP 0.02% of their portfolio | 1.7m $127.4m | Added +6.0k |
| STATE STREET CORP 0.00% of their portfolio | 1.6m $120.6m | Reduced -49.4k |
| Vestal Point Capital, LP 2.65% of their portfolio | 1.6m $113.4m | Added +850.0k |
| Atlas Venture Life Science Advisors, LLC 12.56% of their portfolio | 1.5m $110.7m | Unchanged |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 1.4m $100.1m | Reduced -6.4k |
| Frazier Life Sciences Management, L.P. 2.16% of their portfolio | 1.4m $99.1m | Unchanged |
| TCG Crossover Management, LLC 2.36% of their portfolio | 1.3m $98.1m | Unchanged |
| BVF INC/IL 2.16% of their portfolio | 1.2m $84.4m | Reduced -118.7k |
| Woodline Partners LP 0.22% of their portfolio | 958.3k $70.1m | Unchanged |
| Siren, L.L.C. 1.32% of their portfolio | 888.4k $65.0m | Reduced -100.0k |
| Logos Global Management LP 2.76% of their portfolio | 875.0k $64.0m | Added +315.0k |
| Opaleye Management Inc. 5.66% of their portfolio | 855.0k $62.5m | Added +434.0k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 789.7k $57.8m | Added +45.5k |
| Assenagon Asset Management S.A. 0.04% of their portfolio | 768.3k $56.2m | Added +222.1k |
| DEERFIELD MANAGEMENT COMPANY, L.P. 0.50% of their portfolio | 657.0k $48.1m | Unchanged |
| DIMENSIONAL FUND ADVISORS LP 0.01% of their portfolio | 569.0k $41.6m | Added +174.6k |
| Bellevue Group AG 0.86% of their portfolio | 560.0k $41.0m | Added +100.7k |
| Saturn V Capital Management LP 5.50% of their portfolio | 524.7k $38.4m | Added +74.8k |
| ARMISTICE CAPITAL, LLC 0.93% of their portfolio | 460.0k $33.6m | Reduced -76.0k |
| JENNISON ASSOCIATES LLC 0.02% of their portfolio | 439.5k $32.1m | Reduced -170.9k |
| Aberdeen Group plc 0.04% of their portfolio | 438.2k $32.0m | Added +62.6k |
| Palo Alto Investors LP 4.21% of their portfolio | 416.6k $30.5m | Added +14.9k |
| EVENTIDE ASSET MANAGEMENT, LLC 0.39% of their portfolio | 395.7k $28.9m | Added +79 |
| Pictet Asset Management Holding SA 0.03% of their portfolio | 385.4k $28.2m | Reduced -1.6k |
| LOOMIS SAYLES & CO L P 0.04% of their portfolio | 381.9k $27.9m | Added +64.6k |
| Foresite Capital Management V, LLC 7.55% of their portfolio | 374.1k $27.4m | Unchanged |
| ORBIMED ADVISORS LLC 0.50% of their portfolio | 357.5k $26.2m | Reduced -710.0k |
| BAKER BROS. ADVISORS LP 0.13% of their portfolio | 349.7k $25.6m | Unchanged |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.00% of their portfolio | 281.9k $20.6m | Added +34.6k |
| Octagon Capital Advisors LP 1.81% of their portfolio | 270.0k $19.7m | Unchanged |
| NORTHERN TRUST CORP 0.00% of their portfolio | 265.0k $19.4m | Added +17.8k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 257.4k $18.8m | Added +6.2k |
| Checkpoint Capital L.P. 4.51% of their portfolio | 240.1k $17.6m | Reduced -46.5k |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 225.2k $16.5m | Added +7.8k |
| CITADEL ADVISORS LLC 0.01% of their portfolio | 209.3k $15.3m | Added +111.4k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 204.7k $15.0m | Reduced -241 |
| BNP PARIBAS FINANCIAL MARKETS 0.01% of their portfolio | 184.7k $13.5m | Added +57.0k |
| Catalio Capital Management, LP 2.19% of their portfolio | 159.4k $11.7m | Added +36.4k |
| Sofinnova Investments, Inc. 0.57% of their portfolio | 146.2k $10.7m | Added +67.9k |
| Bain Capital Life Sciences Investors, LLC 0.61% of their portfolio | 141.2k $10.3m | Unchanged |
| TWO SIGMA INVESTMENTS, LP 0.01% of their portfolio | 136.8k $10.0m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 135.1k $9.9m | Reduced -31.7k |
| Alyeska Investment Group, L.P. 0.02% of their portfolio | 125.0k $9.1m | Unchanged |
| Ensign Peak Advisors, Inc 0.01% of their portfolio | 122.1k $8.9m | Reduced -69.4k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 114.1k $8.3m | Added +3.2k |
| UBS Group AG 0.00% of their portfolio | 111.0k $8.1m | Added +12.3k |
| Trexquant Investment LP 0.05% of their portfolio | 107.7k $7.9m | New |
| KENNEDY CAPITAL MANAGEMENT LLC 0.14% of their portfolio | 106.8k $7.8m | Reduced -1.5k |
| MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio | 106.2k $7.8m | Added +23.0k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 97.4k $7.1m | Reduced -542.5k |
| MORGAN STANLEY 0.00% of their portfolio | 91.6k $6.7m | Reduced -2.7k |
| HRT FINANCIAL LP 0.02% of their portfolio | 90.8k $6.6m | New |
| SILVERARC CAPITAL MANAGEMENT, LLC 0.67% of their portfolio | 82.8k $6.1m | Reduced -113.2k |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 78.0k $5.7m | Added +33.3k |
| Squarepoint Ops LLC 0.01% of their portfolio | 75.9k $5.5m | Added +44.2k |
| DNB Asset Management AS 0.01% of their portfolio | 73.1k $5.3m | Reduced -23.6k |
| iA Global Asset Management Inc. 0.06% of their portfolio | 66.0k $4.8m | Reduced -220 |
| Casdin Capital, LLC 0.24% of their portfolio | 65.0k $4.8m | Unchanged |
| SPHERA FUNDS MANAGEMENT LTD. 0.66% of their portfolio | 63.5k $4.6m | Added +10.0k |
| Nuveen, LLC 0.00% of their portfolio | 60.4k $4.4m | Added +9.0k |
| KVP Capital Advisors, LP 3.13% of their portfolio | 58.2k $4.3m | Unchanged |
| MOORE CAPITAL MANAGEMENT, LP 0.10% of their portfolio | 57.8k $4.2m | Unchanged |
| XTX Topco Ltd 0.05% of their portfolio | 56.7k $4.1m | Added +22.3k |
| NEXTBio Capital Management LP 1.77% of their portfolio | 52.7k $3.9m | Unchanged |
| ALGERT GLOBAL LLC 0.04% of their portfolio | 51.9k $3.8m | Added +29.2k |
| ExodusPoint Capital Management, LP 0.03% of their portfolio | 51.6k $3.8m | New |
| SCHRODER INVESTMENT MANAGEMENT GROUP 0.00% of their portfolio | 50.0k $3.7m | Reduced -959 |
| Burkehill Global Management, LP 0.13% of their portfolio | 50.0k $3.7m | Unchanged |
| Brevan Howard Capital Management LP 0.05% of their portfolio | 50.0k $3.7m | Added +17.6k |
| Swiss National Bank 0.00% of their portfolio | 49.8k $3.6m | Added +1.8k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 45.9k $3.4m | Added +37 |
| Atle Fund Management AB 0.86% of their portfolio | 43.7k $3.2m | Reduced -63.6k |
| Quadrature Capital Ltd 0.03% of their portfolio | 42.4k $3.1m | New |
| Invesco Ltd. 0.00% of their portfolio | 42.1k $3.1m | Added +11.4k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 39.4k $2.9m | Added +5.0k |
| ALPS ADVISORS INC 0.01% of their portfolio | 38.6k $2.8m | Added +7.5k |
| CITIGROUP INC 0.00% of their portfolio | 38.3k $2.8m | Added +30.6k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.00% of their portfolio | 38.3k $2.8m | Reduced -1.6k |
| Universal- Beteiligungs- und Servicegesellschaft mbH 0.00% of their portfolio | 36.6k $2.7m | Reduced -1.4k |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 35.8k $2.6m | Added +2.8k |
| LAZARD ASSET MANAGEMENT LLC 0.00% of their portfolio | 35.0k $2.6m | Reduced -4.4k |
| SEVEN GRAND MANAGERS, LLC 0.10% of their portfolio | 35.0k $2.6m | Unchanged |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 34.7k $2.2m | Added +10.1k |
| MARSHALL WACE, LLP 0.00% of their portfolio | 34.4k $2.5m | New |
| Jump Financial, LLC 0.02% of their portfolio | 32.5k $2.4m | Reduced -49.3k |
| BANK OF MONTREAL /CAN/ 0.00% of their portfolio | 32.3k $2.4m | Added +3.5k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 30.6k $2.2m | Added +6.2k |
| RTW INVESTMENTS, LP 0.02% of their portfolio | 30.0k $2.2m | Unchanged |
| VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio | 29.1k $2.1m | Reduced -101 |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 28.9k $2.1m | Added +14.2k |
| TUDOR INVESTMENT CORP ET AL 0.01% of their portfolio | 28.7k $2.1m | Reduced -2.3k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 27.8k $2.0m | Reduced -4.7k |
| Y-Intercept (Hong Kong) Ltd 0.04% of their portfolio | 26.9k $2.0m | New |
| Rafferty Asset Management, LLC 0.00% of their portfolio | 26.6k $1.9m | Reduced -27.3k |
| Campbell & CO Investment Adviser LLC 0.10% of their portfolio | 25.6k $1.9m | New |