BARRETT MICHAEL G. 4

What Happened
Michael G. Barrett, CEO and director of Magnite, exercised 75,000 vested stock options at a $5.80 strike (cost $435,000) and immediately sold 75,000 shares in the open market at $19.50 each for $1,462,500. The transactions were reported on Form 4 for the 2026-06-29 trades and were made pursuant to a Rule 10b5-1 trading plan.

Key Details

• Transaction date: 2026-06-29 (reported 2026-07-01). Filing appears timely.
• Exercise: 75,000 options exercised @ $5.80 = $435,000 (acquired).
• Sale: 75,000 shares sold @ $19.50 = $1,462,500 (disposed).
• Derivative line: 75,000 shares listed as disposed at $0 reflects the option conversion/recording related to the exercise.
• Net proceeds before fees/taxes: approximately $1,027,500 (sale proceeds minus exercise cost).
• Footnotes: F1 — trades executed under a 10b5-1 plan adopted March 13, 2026; F2 — options were fully vested and immediately exercisable; F3 — options were granted as compensation.
• Shares owned after transaction: not specified in the provided filing excerpt.

Context
Because the options were vested and the shares were sold immediately under a pre-established 10b5-1 plan, this sequence is consistent with a routine exercise-and-sell (cashless-style) transaction to monetize vested compensation rather than an open-market purchase as a bullish signal. The 10b5-1 plan indicates the sale was prearranged and not a spontaneous trade.