144 0001628098 XXXXXXXX LIVE 0001816736 Disc Medicine, Inc. 001-39438 321 ARSENAL STREET, SUITE 101 WATERTOWN MA 02472 617-674-9274 Atlas Venture Fund X, LP Shareholder Common Stock Merrill Lynch

One Bryant Park New York NY 10036

22666 2085272 37750162 12/16/2025 Nasdaq Common Stock 05/01/2020 Private Placement Issuer N 22666 05/01/2020 Cash Y See attached Table II for sales of securities over the last three months. 12/16/2025 Ommer Chohan