Quick Takeaways
- Atlas Venture Fund X, L.P. filed SCHEDULE 13D/A for DISC MEDICINE, INC. Common Stock, $0.0001 par value per share (IRON).
- Disclosed ownership: 2.2%.
- Date of event: 12 Dec 2025.
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.
- Symbol
- IRON
- Shares outstanding
- 36,962,136 shares
- Disclosed Ownership
- 813,167 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
Quoteable Key Fact
"Atlas Venture Fund X, L.P. disclosed 2.2% ownership in DISC MEDICINE, INC. Common Stock, $0.0001 par value per share (IRON) on 12 Dec 2025."
What Changed
- Previous schedule filing date: 15 Aug 2025.
- Current filing was accepted on 17 Dec 2025, 20:07.
Why This Matters
- This page explains what this Schedule 13D/13G filing tells you before manager-level rows.
- You can verify ownership claims directly against the original SEC filing.
Source Evidence
Backed by Schedule 13D/13G
See Original Filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting Managers (12)
| Name | Ownership | Shares Owned | sole voting power | shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Atlas Venture Fund X, L.P. | 2.2% | 813,167 | 0 | 813,167 | /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% | 813,167 | 0 | 813,167 | /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% | 813,167 | 0 | 813,167 | /s/ Ommer Chohan | Ommer Chohan, CFO | 0001742765 |
| Atlas Venture Fund XII, L.P. | 0% | 14,013 | 0 | 14,013 | /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% | 14,013 | 0 | 14,013 | /s/ Ommer Chohan | By: Atlas Venture Associates XII, LLC, its general partner, By: Ommer Chohan, its CFO | 0001845875 |
| Atlas Venture Associates XII, LLC | 0% | 14,013 | 0 | 14,013 | /s/ Ommer Chohan | Ommer Chohan, CFO | 0001845871 |
| Atlas Venture Opportunity Fund I, L.P. | 0.9% | 349,210 | 0 | 349,210 | /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% | 349,210 | 0 | 349,210 | /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% | 349,210 | 0 | 349,210 | /s/ Ommer Chohan | Ommer Chohan, CFO | 0001780066 |
| Atlas Venture Opportunity Fund II, L.P. | 0.9% | 337,485 | 0 | 337,485 | /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% | 337,485 | 0 | 337,485 | /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% | 337,485 | 0 | 337,485 | /s/ Ommer Chohan | Ommer Chohan, CFO | 0001935810 |