Disc Medicine (IRON) affiliate to sell 71,961 shares on Nasdaq

Rhea-AI Filing Summary

Form 144 notice indicates an intended sale of 71,961 shares of common stock by an affiliate, to be executed through Merrill Lynch on 10/08/2025 on Nasdaq. The filing shows those shares were acquired on 05/01/2020 in a private placement and paid in cash. The filing reports an aggregate market value of $4,885,432.29 for the shares and discloses 34,765,581 shares outstanding. The record of recent sales lists multiple transactions by related Atlas Venture funds from 07/18/2025 through 10/07/2025, showing ongoing dispositions by affiliated holders.

Positive

• Planned sale is transparent via a formal Rule 144 notice with broker and sale date disclosed
• Securities were acquired in a private placement and paid in cash, confirming fully paid status

Negative

• Large affiliated disposals are documented: multiple Atlas Venture fund sales from 07/18/2025 to 10/07/2025
• Proposed block equals a multi‑million dollar market value ($4,885,432.29), representing an on‑market supply event

Insights

Institutional Sales Analyst

Planned block sale of $4.89M by an affiliate ahead of continued recent disposals.

The notice reports a proposed brokered sale of 71,961 common shares on 10/08/2025 through Merrill Lynch. The shares were acquired in a private placement on 05/01/2020 and paid for in cash, which indicates these are vested/paid holdings available for public resale under Rule 144.

Recent sale lines show multiple disposals by related Atlas Venture funds between 07/18/2025 and 10/07/2025, which may affect short‑term supply. Monitor trading on and immediately after 10/08/2025 for any share‑price impact tied to execution size.

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common Stock	Merrill Lynch One Bryant Park New York NY 10036	71961	4885432.29	34765581	10/08/2025	Nasdaq

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common Stock	05/01/2020	Private Placement	Issuer			71961	05/01/2020	Cash

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/18/2025	664	40588.79
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/23/2025	29837	1819239.47
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/24/2025	13033	797188.21
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/30/2025	8492	518329.6
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/05/2025	395	24075.25
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/13/2025	24962	1526501.19
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/14/2025	7212	439848.34
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/22/2025	2287	139584.07
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	10/07/2025	18039	1233536.76
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/18/2025	1184	72375.2
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/23/2025	53215	3244656.91
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/24/2025	23245	1421824.59
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/30/2025	15146	924472.46
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/05/2025	705	42969.75
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/13/2025	44520	2722531.56
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/14/2025	12862	784432.8
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/22/2025	4080	249017.5

144: Remarks and Signature

Remarks

Date of Notice

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

What is the proposed sale for IRON in the Form 144?

The notice offers 71,961 shares of common stock for sale through Merrill Lynch on 10/08/2025 on Nasdaq.

How much are the shares in the Form 144 worth?

The filing states an aggregate market value of $4,885,432.29 for the 71,961 shares.

When and how were the shares being sold acquired?

The shares were acquired on 05/01/2020 in a private placement and payment was made in cash.

Have related parties sold IRON shares recently?

Yes. The filing lists multiple sales by Atlas Venture funds between 07/18/2025 and 10/07/2025, with specific transactions and proceeds disclosed.

How many IRON shares are outstanding according to the filing?

The filing reports 34,765,581 shares outstanding.