Buonasera David 4

What Happened David Buonasera, Chief Technology Officer of Magnite (MGNI), had 8,335 shares disposed/forfeited on May 15, 2026 to satisfy tax withholding associated with vested restricted stock units. The withholding was recorded at $12.82 per share for a total value of $106,855. This was a non‑discretionary forfeiture to cover tax obligations, not an open‑market sale.

Key Details

• Transaction date and price: May 15, 2026 — 8,335 shares @ $12.82 (disposed/forfeited), total $106,855.
• Transaction type: Tax withholding / payment of tax liability (non‑discretionary forfeiture).
• Shares owned after transaction: Not disclosed in this filing.
• Footnotes: F1 confirms the shares were forfeited by the issuer to cover tax withholding on RSU vesting; F2 notes 433 shares were acquired by Buonasera on May 15, 2026 under the company Employee Stock Purchase Plan (ESPP).
• Filing timeliness: Form filed May 19, 2026 reporting a May 15 transaction. Form 4s are typically due within two business days of a reportable transaction, so this filing was submitted several days after the transaction date.

Context This filing documents routine tax withholding tied to equity compensation (vested RSUs). Such forfeitures are standard administrative actions and do not necessarily reflect the insider’s view on the company’s prospects.