Magnite CPO tax-forfeits 9,422 RSU shares, then sells stock

Rhea-AI Filing Summary

Magnite, Inc. reported insider transactions by its Chief Product Officer. On 11/15/2025, 9,422 shares of common stock were forfeited at $14.15 per share to cover tax withholding tied to the vesting of restricted stock units, under an arrangement mandated by the company. After this, the officer held 336,971 shares.

On 11/18/2025, the officer sold 10,857 shares of Magnite common stock at a weighted average price of $13.23 per share, with individual sale prices ranging from $13.13 to $13.30. This sale was executed under a pre-arranged Rule 10b5-1 trading plan adopted on May 28, 2025. Following the reported sale, the officer directly owned 326,114 shares of Magnite common stock.

Insider Trade Summary

Net Seller: 10,857 shares ($143,638)

Net Sell 2 txns

Insider Soroca Adam Lee

Role CHIEF PRODUCT OFFICER

Sold 10,857 shs ($144K)

Type	Security	Shares	Price	Value
Sale	Common Stock	10,857	$13.23	$144K
Tax Withholding	Common Stock	9,422	$14.15	$133K

Holdings After Transaction: Common Stock — 326,114 shares (Direct)

Footnotes (1)

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. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 28, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.13 to $13.30, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote to this Form 4.

Form 4 Insider Transactions: What Each Field Means →

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).

X

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^*

Soroca Adam Lee

(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)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CHIEF PRODUCT OFFICER

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)		9,422	D	$14.15	336,971	D
Common Stock	11/18/2025		S(2)		10,857	D	$13.23(3)	326,114	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.

2. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 28, 2025.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.13 to $13.30, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote to this Form 4.

	/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 transactions did Magnite (MGNI) disclose for its Chief Product Officer?

The Chief Product Officer of Magnite (MGNI) reported two transactions: a forfeiture of 9,422 shares on 11/15/2025 to cover tax withholding on restricted stock unit vesting, and a sale of 10,857 shares on 11/18/2025.

How many Magnite (MGNI) shares does the executive own after these transactions?

After the reported forfeiture and sale, the Chief Product Officer directly owns 326,114 shares of Magnite common stock.

At what prices were the Magnite (MGNI) shares sold in the recent insider trade?

The 10,857 shares sold on 11/18/2025 had a weighted average price of $13.23 per share, with individual trade prices ranging from $13.13 to $13.30.

Why were 9,422 Magnite (MGNI) shares forfeited by the executive?

The 9,422 shares were a non-discretionary forfeiture to cover tax withholding obligations related to the vesting of restricted stock units, under an arrangement mandated by Magnite.

Was the Magnite (MGNI) insider sale done under a Rule 10b5-1 plan?

Yes. The 10,857-share sale on 11/18/2025 was carried out under a Rule 10b5-1 trading plan that the reporting person adopted on May 28, 2025.

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

The reporting person is an officer of Magnite, serving as the company’s Chief Product Officer.