Magnite CEO Sell-to-Cover: 35,951 Shares Sold to Fund Taxes

Rhea-AI Filing Summary

Magnite, Inc. director and CEO Michael G. Barrett reported a non-discretionary sale of 35,951 shares of common stock on 08/18/2025 at a price of $23.85 per share. The filing states the shares were sold to satisfy the reporting person’s tax withholding obligations arising from the settlement of vested Restricted Stock Units; the sale was mandated by the issuer’s sell-to-cover election and not a discretionary trade. After the transaction, the reporting person beneficially owned 249,857 shares, held directly. The Form 4 was signed by an attorney-in-fact on 08/20/2025.

Positive

• Transparent disclosure of an insider sale and reason for the transaction (tax withholding from vested RSUs).
• Compliance with Section 16 reporting, including signature by attorney-in-fact and explanation of sale.
• Insider retains material ownership: 249,857 shares beneficially owned after the transaction.

Negative

• Insider share count reduced by 35,951 shares due to the sale at $23.85 per share.

Insights

Financial Analyst

TL;DR: A routine sell-to-cover of vested RSUs by the CEO; not an active disposition of conviction.

The Form 4 documents the sale of 35,951 shares at $23.85 to satisfy tax withholding on vested restricted stock units. This is a common administrative transaction that reduces share count held by the insider but is explicitly described as mandated by the company’s withholding procedure, indicating no deliberate liquidity-driven selling decision by the CEO. The remaining direct beneficial ownership is 249,857 shares.

Corporate Governance Expert

TL;DR: Compliance-focused disclosure showing required sell-to-cover; supports governance transparency.

The Form 4 provides clear disclosure of an insider sale tied to tax withholding on vested RSUs and includes an explanation that the sale was not discretionary. This filing meets Section 16 reporting obligations and demonstrates adherence to the issuer’s withholding policy. No indicators of unusual trading patterns or undisclosed arrangements are present in the document.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

BARRETT MICHAEL G.

(Last) (First) (Middle)

C/O MAGNITE, INC.

1250 BROADWAY, 15TH FLOOR

(Street)

NEW YORK NY 10001

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
MAGNITE, INC. [ MGNI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CEO

3. Date of Earliest Transaction (Month/Day/Year)
08/18/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/18/2025		S(1)		35,951	D	$23.85	249,857	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. These shares were sold to cover the Reporting Person's tax obligation resulting from the settlement of vested Restricted Stock Units. The sale is mandated by the Issuer's election to require the satisfaction of tax withholding obligations to be funded by sell to cover transactions and does not represent a discretionary transaction by the Reporting Person.

	/s/ Aaron Saltz, attorney-in-fact	08/20/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transaction did MGNI insider Michael G. Barrett report on Form 4?

He reported a sale of 35,951 shares of Magnite common stock on 08/18/2025 at a price of $23.85 per share.

Why were the shares sold according to the Form 4 for MGNI?

The filing states the shares were sold to satisfy tax withholding obligations resulting from the settlement of vested Restricted Stock Units and were mandatory under the issuer’s sell-to-cover election.

How many MGNI shares does Michael G. Barrett beneficially own after the reported sale?

After the transaction he beneficially owned 249,857 shares (direct ownership).

Was the sale by the MGNI reporting person discretionary?

No. The Form 4 explanation specifies the sale was mandated by the issuer’s election to fund tax withholding and was not a discretionary transaction by the reporting person.

When was the Form 4 signed for the reported MGNI transaction?

The Form 4 was signed by an attorney-in-fact on 08/20/2025.