Magnite (MGNI) Rule 144: 14,461 RSU shares slated for sale via Morgan Stanley

Rhea-AI Filing Summary

Magnite, Inc. (MGNI) Rule 144 notice: The filer proposes to sell 14,461 shares of common stock, to be handled by Morgan Stanley Smith Barney LLC, with an approximate aggregate market value of $342,725.70 and an approximate sale date of 08/18/2025 on NASDAQ. The securities were acquired as restricted stock units from the issuer on 08/15/2025 and the stated payment/nature is equity compensation. The filing also discloses an earlier sale by Sean Buckley of 9,692 shares on 05/16/2025 for $152,491.04. By signing, the seller represents they are not aware of any undisclosed material adverse information about the issuer.

Insights

Securities Analyst

TL;DR: Insider plans a modest sale of restricted stock units totaling $342.7k; prior sale of 9,692 shares occurred in May for $152.5k.

The notice shows a proposed sale of 14,461 common shares derived from restricted stock units granted by the issuer on 08/15/2025. The broker is Morgan Stanley Smith Barney and the execution is targeted for NASDAQ on 08/18/2025. The disclosed aggregate value of $342,725.70 implies an average implied price consistent with the filer’s recent transactions. A prior sale by Sean Buckley of 9,692 shares on 05/16/2025 generated $152,491.04, which provides a recent liquidity event for the same account. For investors, these are routine Rule 144 transactions converting compensated equity into marketable shares and do not, by themselves, convey new operational or financial information about Magnite.

Corporate Governance Expert

TL;DR: This is a standard compliance filing documenting insider sale mechanics and the seller’s attestation about material non-public information.

The form documents compliance with Rule 144 disclosure requirements for restricted stock units issued by the company and intended market sale details, including broker, share count, and estimated value. The seller’s signed attestation that no undisclosed material adverse information exists is a standard legal representation. There is no indication of an executed trading plan or 10b5-1 adoption date in the remarks. From a governance perspective, the filing records transparency around insider liquidity but does not indicate governance changes or issues.

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	Morgan Stanley Smith Barney LLC Executive Financial Services 1 New York Plaza 8th Floor New York NY 10004	14461	342725.70	142399305	08/18/2025	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	08/15/2025	Restricted Stock Unit- See Remarks	Issuer			14461	08/15/2025	Equity Compensation

* 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
Sean Buckley c/o Magnite, Inc. 1250 Broadway, 15th Floor New York NY 10001	Common	05/16/2025	9692	152491.04

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 does Magnite's (MGNI) Form 144 disclose about the proposed sale?

The filing shows a proposed sale of 14,461 common shares acquired as restricted stock units on 08/15/2025, with an aggregate market value of $342,725.70, to be sold via Morgan Stanley Smith Barney on NASDAQ around 08/18/2025.

Who is the broker handling the MGNI sale and where will the shares trade?

The broker is Morgan Stanley Smith Barney LLC and the filing lists NASDAQ as the exchange for the approximate sale date.

Did the filer recently sell other Magnite shares?

Yes. The filing discloses a prior sale by Sean Buckley of 9,692 shares on 05/16/2025 for gross proceeds of $152,491.04.

How were the shares being sold acquired?

The shares were acquired as restricted stock units from the issuer on 08/15/2025 and the nature of payment is listed as equity compensation.

Does the Form 144 indicate any undisclosed material information about Magnite?

By signing the notice, the person represents they are not aware of any material adverse information about the issuer that has not been publicly disclosed; the filing itself contains no disclosure of such information.