Magnite is trading at $11.88, down 52% after-hours on September 22, 2026, versus the provided regular-session close of $24.80; no confirmed earnings release, takeover, regulatory action, or other major breaking catalyst explains the move.
- Magnite’s September 21 8-K says Brian Gephart will become CFO on October 1, succeeding retiring CFO David Day; the transition does not clearly explain the decline.
- Markets were relatively stable: Nasdaq rose 0.62%, and S&P 500 fell 0.03%; after-hours volume and liquidity details were unavailable.