[Form 4] Disc Medicine, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Disc Medicine, Inc. (IRON) – Form 4 insider transaction filed 07/11/2025

Chief Executive Officer and Director John D. Quisel reported one option exercise and two open-market sales executed on 07/09/2025 under a Rule 10b5-1 trading plan adopted 02/13/2025.

• Option exercise (Code M): 34,800 shares exercised at $9.86 per share, sourced from a September 1 2021 option award that vests in 48 equal monthly installments.
• Sales (Code S): Entire 34,800 exercised shares were sold the same day in two tranches: 31,207 shares at a weighted-average $55.2312 (range $55.00-$55.99) and 3,593 shares at a weighted-average $56.1995 (range $56.00-$56.33).
• Net share position: Beneficial ownership briefly rose to 196,628 shares post-exercise, but fell back to 161,828 shares after the sales, resulting in no net change versus the pre-transaction stake.

The filing indicates routine liquidity management by the CEO; no company cash flows are affected. Because transactions were pre-planned and the overall ownership level is unchanged, market impact is likely limited.

Positive

• None.

Negative

• CEO monetized 34,800 shares at ~$55–56, which some investors may interpret as reduced confidence despite the neutral net ownership position.

Insights

Financial Analyst

TL;DR: CEO exercised options then sold all 34,800 shares; ownership unchanged, routine 10b5-1 activity, limited signal.

The Form 4 shows John D. Quisel converting low-priced options ($9.86) into common stock and immediately liquidating the shares around $55-$56, capturing a sizable personal gain. Importantly, his final holding of 161,828 shares matches the pre-exercise level, so there is no dilution and no directional change in insider ownership. Because the trades were executed under a 10b5-1 plan adopted months earlier, they are less likely to reflect new information about Disc Medicine’s prospects. From an investor-sentiment perspective, the appearance of insider sales can be viewed cautiously, but the neutral net position and pre-planning largely offset this concern.

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).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Quisel John D

(Last) (First) (Middle)

C/O DISC MEDICINE, INC.

321 ARSENAL STREET, SUITE 101

(Street)

WATERTOWN MA 02472

(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)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

3. Date of Earliest Transaction (Month/Day/Year)
07/09/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	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	07/09/2025		M(1)		34,800	A	$9.86	196,628	D
Common Stock	07/09/2025		S(1)		31,207	D	$55.2312(2)	165,421	D
Common Stock	07/09/2025		S(1)		3,593	D	$56.1995(3)	161,828	D

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
Stock Option (Right to Buy)	$9.86	07/09/2025		M(1)			34,800	(4)	09/13/2031	Common Stock	34,800	$0	115,375	D

Explanation of Responses:

1. The transactions reported by the Reporting Person were effected pursuant to a Rule 10b5-1 trading plan adopted on February 13, 2025.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $55.00 to $55.99, 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) and (3) to this Form 4.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $56.00 to $56.33, inclusive.

4. The shares underlying this option vest in 48 equal monthly installments following September 1, 2021, subject to the Reporting Person's continued service on each such vesting date.

	By: /s/ Rahul Khara, as Attorney-in-Fact	07/11/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did Disc Medicine (IRON) disclose in the July 11 2025 Form 4?

CEO John D. Quisel exercised 34,800 options at $9.86 and sold the same number of shares at ~$55–56 on 07/09/2025.

How many Disc Medicine shares does the CEO now own?

After the reported transactions, Quisel beneficially owns 161,828 common shares.

Were the insider sales pre-planned?

Yes. All transactions were executed under a Rule 10b5-1 trading plan adopted on February 13 2025.

What prices were the shares sold at?

Weighted-average prices were $55.2312 for 31,207 shares (range $55.00–$55.99) and $56.1995 for 3,593 shares (range $56.00–$56.33).

Did the CEO’s net ownership increase or decrease?

Neither. The exercise briefly increased holdings, but subsequent sales returned the stake to its prior level of 161,828 shares.