Magnite (MGNI) president forfeits 11,204 shares to cover RSU taxes

Rhea-AI Filing Summary

Magnite, Inc. President of Operations Katie Seitz Evans reported a routine tax-related share disposition. On May 15, 2026, 11,204 shares of common stock were forfeited at $12.82 per share to cover tax withholding obligations tied to vesting restricted stock units. After this non-discretionary forfeiture, she directly holds 496,840 shares of Magnite common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Evans Katie Seitz

Role President, Operations

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	11,204	$12.82	$144K

Holdings After Transaction: Common Stock — 496,840 shares (Direct, null)

Footnotes (1)

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Key Figures

Shares forfeited for taxes: 11,204 shares Price per share: $12.82 per share Shares held after transaction: 496,840 shares +1 more

4 metrics

Shares forfeited for taxes 11,204 shares Tax-withholding disposition on May 15, 2026

Price per share $12.82 per share Value used for tax-withholding disposition

Shares held after transaction 496,840 shares Direct ownership after tax-withholding forfeiture

Tax-withholding share count 11,204 shares Reported in transactionSummary as taxWithholdingShares

Key Terms

restricted stock units, tax withholding obligations, non-discretionary forfeiture, transaction code F

4 terms

restricted stock units financial

"associated with the vesting of restricted stock units"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

tax withholding obligations financial

"to cover the tax withholding obligations associated with the vesting"

non-discretionary forfeiture financial

"Represents the non-discretionary forfeiture of shares on behalf of the Reporting Person"

transaction code F financial

"transaction_code_description: Payment of exercise price or tax liability by delivering securities"

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).

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^*

Evans Katie Seitz

(Last) (First) (Middle)

C/O MAGNITE, INC.

1250 BROADWAY, 9TH FLOOR

(Street)

NEW YORK NEW YORK 10001

(City) (State) (Zip)

UNITED STATES

(Country)

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)
	President, Operations

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/15/2026

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

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

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

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	05/15/2026		F(1)		11,204	D	$12.82	496,840	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	05/19/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Magnite (MGNI) report for Katie Seitz Evans?

Magnite reported that President of Operations Katie Seitz Evans had 11,204 common shares forfeited. The shares were used to satisfy tax withholding obligations from vesting restricted stock units, a routine, non-discretionary process rather than an open-market sale.

Was the Magnite (MGNI) insider transaction an open-market sale?

No, the transaction was not an open-market sale. The Form 4 describes a tax-withholding disposition where 11,204 shares were forfeited to cover taxes owed on vesting restricted stock units under an arrangement mandated by Magnite.

How many Magnite (MGNI) shares were forfeited for taxes in this Form 4?

The Form 4 shows that 11,204 shares of Magnite common stock were forfeited. These shares covered tax withholding obligations associated with the vesting of restricted stock units and were classified under transaction code F for tax-related disposition.

What price per share was used for the Magnite (MGNI) tax-withholding disposition?

The tax-withholding disposition used a price of $12.82 per Magnite common share. This price applies to the 11,204 forfeited shares used to satisfy tax obligations related to the vesting of restricted stock units held by Katie Seitz Evans.

How many Magnite (MGNI) shares does Katie Seitz Evans hold after this transaction?

After the tax-withholding forfeiture, Katie Seitz Evans directly holds 496,840 Magnite common shares. This post-transaction balance reflects her remaining ownership following the non-discretionary use of 11,204 shares to cover RSU-related tax obligations.

What does transaction code F mean in the Magnite (MGNI) Form 4 filing?

Transaction code F indicates a disposition to pay taxes or exercise costs using shares. In this case, 11,204 Magnite shares were forfeited to cover tax withholding obligations tied to the vesting of restricted stock units, not a discretionary sale.