Barbara J. Comly, EVP, General Counsel and Corporate Secretary of Miami International Holdings, Inc., filed a Form 4 on September 4, 2026, reporting the exercise of stock options and the same-day sale of 44,445 shares of common stock on September 2, 2026, pursuant to a pre-established Rule 10b5-1 trading plan.

Key Highlights

  • Option exercise: Comly acquired 44,445 shares of common stock via exercise of nonqualified stock options at a conversion price of $12 per share on September 2, 2026.
  • Same-day sale: Comly disposed of 44,445 shares at a weighted average price of $40.49, with individual trades ranging from $39.66 to $41.80 throughout the day.
  • 10b5-1 plan: Both transactions were effected pursuant to a Rule 10b5-1 plan adopted by Comly on December 18, 2025.
  • Remaining ownership: Following the transactions, Comly directly owns 839,564 shares of common stock.
  • Remaining options: Comly retains 44,444 nonqualified stock options, fully vested, with an exercise price of $12 and an expiration date of May 28, 2028.

Comly's Option Exercise and Sale Reported Under Rule 10b5-1 Plan

According to the filing, Barbara J. Comly, serving as EVP, GC and Corporate Secretary at Miami International Holdings, Inc. (MIAX), executed two linked transactions on September 2, 2026. First, she exercised nonqualified stock options to acquire 44,445 shares of common stock at an exercise price of $12 per share, bringing her total directly held shares to 884,009 at that point. The options exercised were described as fully vested in the filing.

Immediately following the exercise, the filing reports that Comly sold the same 44,445 shares. The sale was executed in multiple trades throughout the day at prices ranging from $39.66 to $41.80, with a reported weighted average sales price of $40.49. The filing notes that Comly "undertakes to provide upon request to the Securities and Exchange Commission staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected." After the sale, her direct beneficial ownership stood at 839,564 shares of common stock.

Both transactions were carried out under a Rule 10b5-1 trading plan that Comly adopted on December 18, 2025, according to the filing. The form was signed by Alessandra Maria Corona Henriques as Attorney-in-Fact and filed on September 4, 2026. Separately, Comly retains 44,444 nonqualified stock options with an exercise price of $12 expiring May 28, 2028, also held directly.

What Was Disclosed

The Form 4 filed September 4, 2026, reports that Miami International Holdings EVP Barbara J. Comly exercised 44,445 fully vested stock options at $12 and sold the resulting shares at a weighted average price of $40.49 on September 2, 2026, under a pre-established 10b5-1 plan.