X0609 4 2026-09-02 0 0001438472 MIAMI INTERNATIONAL HOLDINGS, INC. MIAX 0001959770 Teekell Judson Gray false C/O MIAMI INTERNATIONAL HOLDINGS, INC. 7 ROSZEL ROAD, SUITE 1A PRINCETON NJ 08540 1 0 0 0 1 Common Stock 2026-09-02 4 S 0 5545 41.58 D 81000 I By estate of Byrum W. Teekell Common Stock 2026-09-02 4 S 0 3000 40.89 D 69251 D This transaction involved a sale by the Reporting Person in connection with his duties as Executor of the Estate of Byrum W. Teekell. This transaction was executed in multiple trades throughout the day at prices ranging from $41.02 to $41.80. The price reported above reflects the weighted average sales price. The Reporting Person hereby 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. This transaction was effected pursuant to a previously established Rule 10b5-1 Plan adopted by the Reporting Person on December 17, 2025. This transaction was executed in multiple trades throughout the day at prices ranging from $40.31 to $41.53. The price reported above reflects the weighted average sales price. The Reporting Person hereby 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. /s/Alessandra Maria Corona Henriques, Attorney-in-Fact 2026-09-04