X0609 4 2026-08-17 0001816736 Disc Medicine, Inc. IRON 0001586788 Quisel John D false C/O DISC MEDICINE, INC. 321 ARSENAL STREET, SUITE 101 WATERTOWN MA 02472 true true false false Chief Executive Officer true Common Stock 2026-08-17 4 M false 33000 13.50 A 259064 D Common Stock 2026-08-17 4 S false 8400 78.1061 D 250664 D Common Stock 2026-08-17 4 S false 12712 79.1952 D 237952 D Common Stock 2026-08-17 4 S false 11888 79.8420 D 226064 D Stock Option (Right to Buy) 13.50 2026-08-17 4 M false 33000 0 D 2032-12-28 Common Stock 33000 91586 D These transactions were effected by the Reporting Person pursuant to a Rule 10b5-1 trading plan adopted on March 12, 2026. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $77.50 to $78.49, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2), (3) and (4) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $78.53 to $79.52, inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $79.53 to $80.02, inclusive. The shares underlying this option vest in 48 equal monthly installments following December 29, 2022, subject to the Reporting Person's continued service on each such vesting date. By: /s/ Rahul Khara, as Attorney-in-Fact 2026-08-18