Gallagher Thomas P. 4

What Happened Thomas P. Gallagher, Chairman, CEO and a director of Miami International Holdings, Inc. (MIAX), exercised 24,999 stock options on May 11, 2026, at a $12.00 exercise price, resulting in an acquisition valued at $299,988. The filing also reports a matching disposition/conversion of 24,999 derivative units at $0.00 for the same date — the filing lists both the option exercise (acquisition) and the derivative conversion/disposition.

Key Details

• Transaction date: May 11, 2026; Filing date: May 13, 2026 (appears filed within two business days).
• Exercise: 24,999 shares exercised at $12.00 → total paid $299,988.
• Derivative disposition: 24,999 shares reported disposed/converted at $0.00 (derivative entry).
• Footnote: F1 — The options are fully vested.
• Shares owned after transaction: Not specified in this Form 4.

Context

• This was an option exercise (transaction code M). The paired "disposed" entry at $0.00 typically reflects the conversion/retirement of the derivative instrument tied to the exercise; the filing does not show an immediate open‑market sale of the acquired shares for cash.
• Option exercises are routine for executives with vested awards and are not, by themselves, a clear signal of sentiment. This filing is factual reporting of the exercise and conversion.