[144] Disc Medicine, Inc. SEC Filing

Rhea-AI Filing Summary

Disc Medicine (IRON) filed a Form 144 proposing the sale of 44,520 shares of common stock with an aggregate market value of $2,628,015.60, to be sold through Merrill Lynch on Nasdaq. The shares were acquired in a private placement on 05/01/2020 and the filing lists an approximate sale date of 08/13/2025. The filing also discloses multiple recent dispositions by Atlas Venture-related funds: a total of 145,916 shares sold in the past three months, generating approximately $8,905,720.24 in gross proceeds. The issuer has 34,765,581 shares outstanding per the form.

Positive

• None.

Negative

• Substantial recent dispositions: Atlas Venture funds sold a combined 145,916 shares in the past three months for about $8,905,720.24.
• Additional proposed sale: The Form 144 seeks to sell 44,520 shares valued at $2,628,015.60 via Merrill Lynch on Nasdaq.
• Affiliated selling: Sellers listed include Atlas Venture Fund X and Atlas Venture Opportunity Fund I, indicating continued affiliated/insider liquidity events.

Insights

Securities Analyst

TL;DR: Form 144 shows continued affiliated selling: a 44,520-share proposed sale and substantial recent dispositions totaling 145,916 shares.

The Form 144 documents a proposed sale of 44,520 shares ($2,628,015.60) acquired in a private placement on 05/01/2020, with sales handled by Merrill Lynch on Nasdaq. The filing also lists ten transactions by Atlas Venture funds over July–August 2025 totaling 145,916 shares for approximately $8,905,720.24. For investors, these are material ownership movements by affiliated holders; the transactions are factual disclosures rather than operational updates.

Corporate Governance Expert

TL;DR: Multiple large-scale sales by Atlas Venture entities and a new Form 144 filing may raise governance and insider-sentiment questions for shareholders.

The record shows coordinated dispositions by Atlas Venture Fund X and Atlas Venture Opportunity Fund I across July and August 2025, and a further proposed sale of 44,520 shares ($2.63M). The shares were originally acquired in a private placement on 05/01/2020. While the filing is procedural, the scale and timing of affiliated selling documented here are relevant to assessments of insider confidence and ownership concentration.

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	44520	2628015.60	34765581	08/13/2025	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			44520	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 Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/18/2025	1184	72375.20
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/18/2025	664	40588.80
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/23/2025	53215	3244656.91
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/23/2025	29837	1819239.47
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/24/2025	23245	1421824.59
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/24/2025	13033	797188.21
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/30/2025	15146	924472.46
Atlas Venture Opportunity Fund I, LP. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	07/30/2025	8492	518329.60
Atlas Venture Fund X, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/05/2025	705	42969.75
Atlas Venture Opportunity Fund I, L.P. 300 Technology Sq Ste 8 Cambridge MA 02139	Common Stock	08/05/2025	395	24075.25

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

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 does the Form 144 for Disc Medicine (IRON) announce?

The Form 144 notifies a proposed sale of 44,520 shares with an aggregate market value of $2,628,015.60, to be executed through Merrill Lynch on Nasdaq.

When were the shares proposed for sale originally acquired?

The shares were acquired in a private placement on 05/01/2020, with cash noted as the payment method.

How many shares were sold by Atlas Venture funds in the past three months?

Atlas Venture Fund X and Atlas Venture Opportunity Fund I sold a combined total of 145,916 shares in the past three months.

What were the gross proceeds from recent Atlas Venture sales?

The ten listed transactions generated approximately $8,905,720.24 in gross proceeds over July–August 2025.

How many shares outstanding does the filing report for the issuer?

The filing reports 34,765,581 shares outstanding for the issuer.