SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Atlas Venture Fund X, L.P. (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Disc Medicine, Inc. [ IRON ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 12/29/2022
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	12/29/2022		J(1)		1,835,799	A	(1)(2)	2,237,303	D(3)
Common Stock	12/29/2022		J(1)		882,224	A	(1)(2)	955,156	I	See Footnote(4)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* Atlas Venture Fund X, L.P. (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

1. Name and Address of Reporting Person* ATLAS VENTURE ASSOCIATES X, L.P. (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

1. Name and Address of Reporting Person* Atlas Venture Associates X, LLC (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

1. Name and Address of Reporting Person* Atlas Venture Opportunity Fund I, L.P. (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

1. Name and Address of Reporting Person* Atlas Venture Associates Opportunity I, L.P. (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

1. Name and Address of Reporting Person* Atlas Venture Associates Opportunity I, LLC (Last) (First) (Middle) 300 TECHNOLOGY SQUARE, 8TH FLOOR (Street) CAMBRIDGE MA 02139 (City) (State) (Zip)

Explanation of Responses:

1. Gemini Therapeutics, Inc. (" Gemini"), and Disc Medicine Opco, Inc. (f/k/a Disc Medicine, Inc.) ("Disc"), entered into an Agreement and Plan of Merger and Reorganization (the "Merger Agreement"), on August 9, 2022, pursuant to which, among other matters, a direct, wholly owned subsidiary of Gemini, Gemstone Merger Sub, Inc. ("Merger Sub"), merged with and into Disc, with Disc surviving as a wholly owned subsidiary of Gemini, and the surviving corporation of the merger, which transaction is referred to herein as the merger. The merger closed on on December 29, 2022. Following the effectiveness of the merger on December 29, 2022, the surviving corporation changed its name from Gemini to Disc Medicine, Inc. (the "Issuer").

2. (Continued from footnote 1) Upon the closing of the merger, each share of Disc common stock (after giving effect to the conversion of each share of Disc's preferred stock into Disc common stock and including all such shares that are converted into Disc common stock) was converted into the right to receive a number of shares of Gemini common stock equal to an exchange ratio of 0.1096.

3. These shares are held directly by Atlas Venture Fund X, L.P. ("Atlas X"). Atlas Venture Associates X, L.P. ("Associates X") is the general partner of Atlas X. Atlas Venture Associates X, LLC ("Associates X LLC") is the general partner of Associates X. Each of Associates X and Associates X LLC disclaims Section 16 beneficial ownership of the securities held by Atlas X, except to the extent of its pecuniary interest therein, if any.

4. These shares are held directly by Atlas Venture Opportunity Fund I, L.P. ("Atlas Opportunity I"). Atlas Venture Associates Opportunity I, L.P. ("Associates I") is the general partner of Atlas Opportunity I. Atlas Venture Associates Opportunity I, LLC ("Associates I LLC") is the general partner of Associates I. Each of Associates I and Associates I LLC disclaims Section 16 beneficial ownership of the securities held by Atlas Opportunity I, except to the extent of its pecuniary interest therein, if any.

Remarks:

	Atlas Venture Fund X, L.P., By: Atlas Venture Associates X, L.P., its general partner, By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	Atlas Venture Associates X, L.P., By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	Atlas Venture Associates X, LLC By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	Atlas Venture Opportunity Fund I, L.P., By: Atlas Venture Associates Opportunity I, L.P., its general partner, By: Atlas Venture Associates Opportunity I, LLC, its general partner, By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	Atlas Venture Associates Opportunity I, L.P., By: Atlas Venture Associates Opportunity I, LLC, its general partner, By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	Atlas Venture Associates Opportunity I, LLC By: Ommer Chohan, Chief Financial Officer /s/ Ommer Chohan	01/03/2023
	** Signature of Reporting Person	Date
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