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

Rhea-AI Filing Summary

Disc Medicine, Inc. (IRON) – CEO Form 4 filing dated 07/08/2025

Chief Executive Officer John D. Quisel disclosed an exercise-and-sell transaction executed on 07/03/2025 under a Rule 10b5-1 trading plan adopted on 02/13/2025.

• Option exercise (Code M): 5,200 options exercised at $9.86, converting into 5,200 common shares.
• Open-market sale (Code S): the same 5,200 shares sold at a $55.0874 weighted-average price (range $55.00–$55.26), generating ≈ $0.29 million gross proceeds.
• Post-transaction ownership: 161,828 common shares held directly and 150,175 options remaining.
• The underlying option grant (09/13/2031 expiration) vests in 48 equal monthly tranches that began on 09/01/2021.

The filing represents a relatively small (< 4%) reduction in Quisel’s equity stake and appears routine, given the pre-arranged 10b5-1 plan. No company fundamentals were released.

Positive

• None.

Negative

• Insider sale by CEO can be perceived negatively by some investors, though size is modest.

Insights

Financial Analyst

TL;DR – Routine 5,200-share sale by CEO; modest size, limited impact.

The CEO’s net sale (~$235k after exercise cost) is minor versus his remaining 161.8k-share holding and 150.2k vested/unvested options. Execution under a disclosed 10b5-1 plan limits signaling risk. While investors often view insider sales warily, the small percentage and continued sizable ownership suggest no material change in management’s alignment. Overall impact on valuation and sentiment should be neutral.

Corporate Governance Expert

TL;DR – Sale compliant with Rule 10b5-1; governance posture intact.

The transaction follows best-practice governance: advance 10b5-1 plan, same-day exercise-and-sale, and full price-range disclosure. No red flags on timing or volume. Continual vesting schedule aligns long-term incentives. From a governance standpoint, the filing is non-impactful.

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)
07/03/2025

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	07/03/2025		M(1)		5,200	A	$9.86	167,028	D
Common Stock	07/03/2025		S(1)		5,200	D	$55.0874(2)	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	07/03/2025		M(1)			5,200	(3)	09/13/2031	Common Stock	5,200	$0	150,175	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 $55.26, 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 range set forth in this footnote (2) to this Form 4.

3. 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	07/08/2025
	** 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

Why did Disc Medicine’s CEO sell shares on 07/03/2025?

The 5,200-share sale was executed under a pre-arranged Rule 10b5-1 trading plan adopted on 02/13/2025.

How many Disc Medicine (IRON) shares does CEO John Quisel still own?

After the transaction, he directly owns 161,828 common shares and holds 150,175 options.

At what price were the shares sold according to the Form 4?

The weighted-average sale price reported was $55.0874, within a $55.00–$55.26 range.

What was the exercise price of the stock options?

The options were exercised at $9.86 per share.

Do the remaining options have an expiration date?

Yes. The reported option lot expires on 09/13/2031.

Is the insider sale considered large relative to the CEO’s stake?

No. The 5,200 shares represent less than 4 % of his post-transaction common-stock holdings.