Magnite (MGNI) CFO forfeits shares to cover RSU tax withholding

Rhea-AI Filing Summary

Magnite, Inc.’s chief financial officer David Day reported a routine share disposition tied to taxes, not an open-market trade. On the vesting of restricted stock units, 14,170 shares of common stock were automatically forfeited at a value of $12.82 per share to cover tax withholding obligations mandated by the company. After this non-discretionary tax-withholding event, Day directly holds 493,289 shares of Magnite common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Day David

Role CHIEF FINANCIAL OFFICER

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	14,170	$12.82	$182K

Holdings After Transaction: Common Stock — 493,289 shares (Direct, null)

Footnotes (1)

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Key Figures

Tax-withholding shares: 14,170 shares Tax-withholding price: $12.82 per share Shares held after transaction: 493,289 shares

3 metrics

Tax-withholding shares 14,170 shares Shares forfeited to cover tax obligations on RSU vesting

Tax-withholding price $12.82 per share Value used for tax-withholding disposition

Shares held after transaction 493,289 shares CFO’s direct Magnite common stock holdings following the Form 4 event

Key Terms

restricted stock units, tax withholding obligations, non-discretionary forfeiture, Form 4

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"

Form 4 regulatory

"What type of Form 4 transaction code was used"

Form 4 is a official document that company insiders, such as executives or major shareholders, file with regulators whenever they buy or sell company shares. It provides transparency about how those with inside knowledge are trading, helping investors see if insiders are confident in the company's prospects or may be selling for personal reasons. This information can influence investor decisions by revealing insiders' perspectives on the company's value.

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^*

Day David

(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)
	CHIEF FINANCIAL OFFICER

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)		14,170	D	$12.82	493,289	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) CFO David Day report?

Magnite CFO David Day reported an automatic forfeiture of 14,170 common shares. The shares were surrendered to cover tax withholding obligations triggered by the vesting of restricted stock units, rather than through an open-market sale or discretionary transaction.

Was the Magnite (MGNI) CFO’s Form 4 a stock sale in the market?

No, the Form 4 reflects a non-discretionary forfeiture of shares for tax withholding. The shares were delivered back under a company-mandated arrangement related to restricted stock unit vesting, not sold by the CFO on the open market.

How many Magnite (MGNI) shares were used for the CFO’s tax withholding?

A total of 14,170 Magnite common shares were used to satisfy tax withholding obligations. The value used for this tax-withholding disposition was $12.82 per share, according to the reported transaction details in the Form 4 filing.

How many Magnite (MGNI) shares does the CFO hold after this Form 4?

Following the tax-withholding disposition, CFO David Day directly holds 493,289 Magnite common shares. This post-transaction figure reflects his remaining direct ownership after 14,170 shares were forfeited to cover tax obligations tied to RSU vesting.

What type of Form 4 transaction code was used in the Magnite (MGNI) filing?

The transaction used code F, indicating payment of tax liability by delivering securities. This code signifies a tax-withholding disposition associated with equity compensation, rather than a voluntary purchase or sale of Magnite shares by the reporting person.