Magnite CEO reports 12,198 MGNI shares withheld for RSU taxes

Rhea-AI Filing Summary

Magnite, Inc. reported an insider equity transaction by its CEO and director. On 11/15/2025, the reporting person disposed of 12,198 shares of Magnite common stock at a price of $14.15 per share. This disposition is identified with transaction code "F," which indicates that the shares were withheld by the company to satisfy tax withholding obligations.

After this tax-related forfeiture tied to the vesting of restricted stock units, the reporting person beneficially owns 237,659 shares of Magnite common stock in direct ownership. The filing notes that the forfeiture was non-discretionary and mandated by Magnite under an arrangement designed to cover the reporting person’s tax liabilities arising from equity compensation.

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
Estimated average burden
hours per response:			0.5

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, 9TH 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)
11/15/2025

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	11/15/2025		F(1)		12,198	D	$14.15	237,659	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. Represents the non-discretionary forfeiture of shares on behalf of the Reporting Person pursuant to an arrangement mandated by the Issuer to cover the tax withholding obligations associated with the vesting of restricted stock units.

	/s/ Aaron Saltz, attorney-in-fact	11/18/2025
	** 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 insider transaction did Magnite (MGNI) disclose in this Form 4?

Magnite reported that its CEO and director disposed of 12,198 shares of common stock on 11/15/2025 in a transaction coded "F" related to tax withholding on vested restricted stock units.

Why were 12,198 Magnite (MGNI) shares disposed of in this filing?

The 12,198 shares were non-discretionarily forfeited to cover tax withholding obligations associated with the vesting of restricted stock units, under an arrangement mandated by Magnite.

What transaction code is used in this Magnite (MGNI) Form 4 and what does it mean?

The filing uses transaction code "F", which denotes a transaction in which shares are withheld by the issuer to pay tax obligations related to an equity award, rather than an open-market sale.

How many Magnite (MGNI) shares does the reporting person own after this transaction?

Following the reported tax-withholding transaction, the reporting person beneficially owns 237,659 shares of Magnite common stock in direct ownership.

What is the role of the reporting person at Magnite (MGNI)?

The reporting person is identified as both a director and an officer, serving as CEO of Magnite, Inc.

Was this Magnite (MGNI) insider transaction part of a discretionary trading plan?

No. The explanation states that the forfeiture was non-discretionary and mandated by Magnite to cover tax withholding obligations from restricted stock unit vesting.