MGNX (NASDAQ: MGNX) holder files to sell 20,166 common shares under Rule 144

Rhea-AI Filing Summary

MGNX has a notice covering a planned sale of common stock under Rule 144. A holder intends to sell up to 20,166 shares of common stock through Merrill Lynch, with a proposed sale date of 08/03/2026 on the NASDAQ. The shares were obtained via stock plan activity on several dates, including 05/20/2024, 05/20/2025, and 05/18/2026.

Key Figures

Planned shares to be sold: 20,166 shares Proposed sale date: 08/03/2026 Shares acquired 05/18/2026: 3,750 shares +2 more

5 metrics

Planned shares to be sold 20,166 shares Common stock to be sold under Rule 144 on or after 08/03/2026

Proposed sale date 08/03/2026 Proposed sale date for 20,166 shares of common stock

Shares acquired 05/18/2026 3,750 shares Common shares acquired via stock plan activity on 05/18/2026

Shares acquired 05/20/2025 6,500 shares Common shares acquired via stock plan activity on 05/20/2025

Shares acquired 05/20/2024 4,500 shares Common shares acquired via stock plan activity on 05/20/2024

Key Terms

Rule 144, stock plan activity, Securities To Be Sold

3 terms

Rule 144 regulatory

"A holder intends to sell shares of common stock under Rule 144."

Rule 144 is a U.S. securities regulation that sets conditions under which restricted or insider-held shares can be legally resold to the public, such as required holding periods, availability of public information, limits on how much can be sold at once, and certain filing requirements. For investors it matters because it determines when previously locked-up shares can enter the market — like a release valve that can increase supply, affect share price, and signal insider intent.

stock plan activity financial

"Common | 05/18/2026 | Stock plan activity | Issuer"

Securities To Be Sold regulatory

"144: Securities To Be Sold Common | 08/03/2026 | Stock plan activity"

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 08/03/2026 - 04:31 PM Accepted by SEC EDGAR 08/03/2026 - 04:30 PM Learn about SEC filing dates

FAQ

What does the Form 144 filing for MGNX disclose?

The Form 144 discloses that a holder of MGNX common stock plans to sell up to 20,166 shares under Rule 144, with Merrill Lynch as broker and trading on the NASDAQ on or after 08/03/2026.

How many MGNX shares are planned to be sold under this Form 144?

The planned sale covers up to 20,166 shares of MGNX common stock. This amount appears in the “Securities To Be Sold” section, associated with a proposed sale date of 08/03/2026 and trading on the NASDAQ market.

When are the MGNX shares expected to be sold according to the Form 144?

The proposed sale date for the 20,166 shares of MGNX common stock is 08/03/2026. This date appears in the securities information and is tied to the planned Rule 144 transaction through Merrill Lynch on the NASDAQ.

How were the MGNX shares in this Form 144 acquired?

The shares covered by the Form 144 were acquired through stock plan activity. Acquisition dates listed include 05/20/2024, 05/20/2025, and 05/18/2026, reflecting grants or issuances under an issuer stock plan.

Does the MGNX Form 144 list any sales in the past three months?

The Form 144 includes a section for “Securities Sold During The Past 3 Months”, but no specific share amounts or dates are shown there in the provided content for MGNX.

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	Merrill Lynch 1800 K St NW Suite 800 Washington DC 20006	34916	130935	63563123	08/03/2026	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	08/03/2026	Stock plan activity	Issuer			20166	08/03/2026	n/a
Common	05/18/2026	Stock plan activity	Issuer			3750	05/18/2026	n/a
Common	05/20/2025	Stock plan activity	Issuer			6500	05/20/2025	n/a
Common	05/20/2024	Stock plan activity	Issuer			4500	05/20/2024	n/a

* 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

Nothing to Report

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)