Magnite Insider Barrett Files Form 144 for July 2025 Share Sale

Rhea-AI Filing Summary

Magnite, Inc. (NASDAQ: MGNI) has filed a Form 144 indicating that Chief Executive Officer Michael Barrett intends to sell up to 70,900 common shares around 15 July 2025. The proposed sale, to be executed through Raymond James & Associates, is valued at approximately $1.65 million based on the filing’s reference price, and represents roughly 0.05 % of the company’s 135.6 million shares outstanding.

The notice also discloses that Barrett acquired the shares earlier in 2025 as restricted stock grants (31,377 shares on 5 Feb; 25,405 on 15 Feb; 14,118 on 15 May). In addition, the CEO sold a total of 375,000 shares during June 2025 for gross proceeds of $7.37 million, underscoring a pattern of recent insider selling.

While the absolute number of shares is small relative to the public float, the consecutive transactions may influence investor sentiment, especially given the seller’s senior role. The filing contains no indication that the sale is linked to a 10b5-1 trading plan, although it references Rule 10b5-1 compliance language. Investors typically monitor such activity for potential signals about management’s outlook, liquidity needs, or portfolio diversification.

Key figures:

• Shares to be sold: 70,900
• Aggregate market value: $1,650,160
• Broker: Raymond James & Associates
• Approximate sale date: 15 July 2025
• Shares sold in prior 3 months: 375,000 (gross proceeds $7.37 M)

Given the limited size versus total outstanding shares, the transaction is unlikely to have a material impact on Magnite’s capitalization but may attract short-term scrutiny regarding insider confidence.

Insights

Securities Analyst

TL;DR: Modest CEO sale (0.05 % float); sentiment-negative but financially immaterial.

The proposed 70.9 k-share sale is negligible relative to Magnite’s 135.6 M shares outstanding and should not affect liquidity or valuation fundamentals. However, cumulative insider disposals of 445.9 k shares in six weeks could weigh on near-term sentiment, particularly amid ad-tech sector volatility. Lack of an explicit 10b5-1 plan elevates perception risk. Overall impact on intrinsic value is de minimis; monitor for continuing sales cadence.

Corporate Governance Expert

TL;DR: Repeated CEO selling without disclosed 10b5-1 plan raises governance optics.

Investors view sustained insider selling by top executives as a potential red flag unless tied to a pre-arranged diversification strategy. While Barrett’s sale size is small, transparency around objectives and trading-plan status would mitigate concerns. The filing fulfills SEC disclosure requirements, yet governance best practice favors clearer communication to avoid misinterpretation of leadership confidence levels.

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

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	Raymond James & Associates 880 Carillon Parkway St. Petersburg FL 33716	70900	1650160.00	135574532	07/15/2025	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	02/05/2025	Restricted	Issuer			31377	02/05/2025	N/A
Common	02/15/2025	Restricted	Issuer			25405	02/15/2025	N/A
Common	05/15/2025	Restricted	Issuer			14118	05/15/2025	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

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
Michael Barrett 1250 Broadway, 15th Floor New York NY 10001	Common	06/16/2025	45000	799000.00
Michael Barrett 1250 Broadway, 15th Floor New York NY 10001	Common	06/18/2025	30000	570000.00
Michael Barrett 1250 Broadway, 15th Floor New York NY 10001	Common	06/24/2025	300000	6000000.00

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 is Magnite’s (MGNI) Form 144 about?

It notifies the SEC that CEO Michael Barrett intends to sell 70,900 common shares around 15 July 2025.

How many MGNI shares has the CEO sold recently?

The filing lists 375,000 shares sold in June 2025 and a proposed 70,900-share sale in July 2025.

What percentage of Magnite’s shares does the proposed sale represent?

About 0.05 % of the 135.6 million shares outstanding.

What is the estimated value of the shares to be sold?

The aggregate market value is approximately $1.65 million.

Which broker will handle the transaction?

Raymond James & Associates, 880 Carillon Parkway, St. Petersburg, FL 33716.

Does the filing mention a Rule 10b5-1 trading plan?

The standard representation language is included, but the document does not explicitly state that the sale is under a 10b5-1 plan.