Atlas Venture Fund X, L.P. - 12 Dec 2025 SCHEDULE 13D/A Report for DISC MEDICINE, INC. Common Stock, $0.0001 par value per share (IRON)

Filing Manager
Atlas Venture Fund X, L.P.
Reporting Manager
Atlas Venture Fund X, L.P.
Security
DISC MEDICINE, INC. Common Stock, $0.0001 par value per share
Symbol
IRON
Shares outstanding
37M shares
Disclosed Ownership
813K shares
Ownership
2.2%
Form type
SCHEDULE 13D/A
Filing time
17 Dec 2025, 20:07:46 UTC
Date of event
12 Dec 2025
Previous filing
15 Aug 2025
SEC
View on sec.gov

Reporting Managers (12)

Name Ownership Shares Owned sole voting power shared voting power Signature Title CIK
Atlas Venture Fund X, L.P. 2.2% 813K 0 813K /s/ Ommer Chohan By: Atlas Venture Associates X, L.P., its general partner, By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, its CFO 0001628098
ATLAS VENTURE ASSOCIATES X, L.P. 2.2% 813K 0 813K /s/ Ommer Chohan By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, its CFO 0001742766
Atlas Venture Associates X, LLC 2.2% 813K 0 813K /s/ Ommer Chohan Ommer Chohan, CFO 0001742765
Atlas Venture Fund XII, L.P. 0% 14K 0 14K /s/ Ommer Chohan By: Atlas Venture Associates XII, L.P., its general partner, By: Atlas Venture Associates XII, LLC, its general partner, By: Ommer Chohan, its CFO 0001812049
Atlas Venture Associates XII, L.P. 0% 14K 0 14K /s/ Ommer Chohan By: Atlas Venture Associates XII, LLC, its general partner, By: Ommer Chohan, its CFO 0001845875
Atlas Venture Associates XII, LLC 0% 14K 0 14K /s/ Ommer Chohan Ommer Chohan, CFO 0001845871
Atlas Venture Opportunity Fund I, L.P. 0.9% 349K 0 349K /s/ Ommer Chohan By: Atlas Venture Associates Opportunity I, L.P., its G.P., By: Atlas Venture Associates Opportunity I, LLC, its G.P., By: Ommer Chohan, CFO 0001759241
Atlas Venture Associates Opportunity I, L.P. 0.9% 349K 0 349K /s/ Ommer Chohan By: Atlas Venture Associates Opportunity I, LLC, its General Partner, By: Ommer Chohan, CFO 0001780065
Atlas Venture Associates Opportunity I, LLC 0.9% 349K 0 349K /s/ Ommer Chohan Ommer Chohan, CFO 0001780066
Atlas Venture Opportunity Fund II, L.P. 0.9% 337K 0 337K /s/ Ommer Chohan By: Atlas Venture Associates Opportunity II, L.P., its G.P., By: Atlas Venture Associates Opportunity II, LLC, its G.P., By: Ommer Chohan, CFO 0001885327
Atlas Venture Associates Opportunity II, LP 0.9% 337K 0 337K /s/ Ommer Chohan By: Atlas Venture Associates Opportunity II, LLC, its General Partner, By: Ommer Chohan, CFO 0001935814
Atlas Venture Associates Opportunity II, LLC 0.9% 337K 0 337K /s/ Ommer Chohan Ommer Chohan, CFO 0001935810