Brian Gephart - 15 May 2026 Form 4 Insider Report for MAGNITE, INC. (MGNI)

Reporting relationship: CHIEF ACCOUNTING OFFICER
Issuer ticker: MGNI
Reported as of: 15 May 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 19 May 2026, 17:00:15 UTC
Prior SEC filing: 18 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Aaron Saltz, attorney-in-fact

Key filing fact

Brian Gephart filed Form 4 for MAGNITE, INC. (MGNI) on 19 May 2026.

Key facts

This page summarizes Brian Gephart's Form 4 filing for MAGNITE, INC. (MGNI).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 19 May 2026, 17:00.

Change

Previous filing in this sequence was filed on 18 Feb 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001778484 Primary reporting owner

Gephart Brian

Relationship: CHIEF ACCOUNTING OFFICER
Address: C/O MAGNITE, INC., 1250 BROADWAY, 9TH FLOOR, NEW YORK
Signature: /s/ Aaron Saltz, attorney-in-fact
Signature date: 19 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MGNI transaction

Common Stock

Tax liability

Transaction value
Shares: -3,789
Change %: -3.1%
Price: $12.82^*
Shares after: 118,596
Date: 15 May 2026
Ownership: Direct
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 1 footnote

Footnote F1

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.