Teekell Judson Gray 4

What Happened

• Teekell Judson Gray, a director of Miami International Holdings, Inc. (MIAX), exercised 22,667 stock options on May 19, 2026, at an exercise price of $12.00 per share, representing $272,004 in value.
• To cover the exercise price/tax liability, 4,991 shares were withheld by the issuer (valued at about $54.51 each, ~$272,059) — this withholding is not an open-market sale. Net shares received by Gray = 22,667 − 4,991 = 17,676 shares.
• The derivative position was converted/settled as part of the exercise (reported as a zero-dollar disposition of the derivative).

Key Details

• Transaction date: 2026-05-19.
• Option exercise: 22,667 shares acquired at $12.00 each (total $272,004) — code M (exercise).
• Withholding: 4,991 shares withheld to cover exercise price/taxes at $54.51 each (total ~$272,059) — code F (tax/payment withholding); issuer withholding, not a sale (Footnote F1).
• Options were fully vested at time of exercise (Footnote F2).
• Shares owned after the transaction: not reported in the provided filing.
• Filing date/Period of report: 2026-05-19 — appears timely (no late filing indicated).

Context

• This was effectively a cashless exercise: options converted to shares and a portion of the shares was withheld to satisfy payment/tax obligations, rather than shares being sold on the open market.
• Withholding to cover exercise/taxes is a routine administrative step and does not necessarily signal a voluntary sale by the insider.