X0609 4 2026-05-19 1 0001438472 MIAMI INTERNATIONAL HOLDINGS, INC. MIAX 0001056823 HORIZON KINETICS ASSET MANAGEMENT LLC false 470 PARK AVE S 8TH FLOOR SOUTH NEW YORK NY 10016 1 0 Common Stock 2026-05-19 4 J 0 2455744 0 D 2170898 I Horizon Kinetics Asset Management LLC On May 21, 2026, Horizon Kinetics Asset Management LLC ("HKAM") filed an amendment to its Schedule 13D wherein it reported beneficial ownership of 7,400,316 shares or 7.8 percent of the outstanding shares of the Issuer. The extent of HKAM's pecuniary interest in the shares reported in the Schedule 13D are disclosed herein. The change represents a reduction of 2,455,744 shares that were distributed in-kind on a pro rata basis, without consideration. This amount reflects a reduction of 7,200 shares that were held in an account for which the Reporting Person no longer has a pecuniary interest. Murray Stahl previously served as a Director of the Issuer and the Chairman, Chief Executive Officer and Chief Investment Officer of Horizon Kinetics Asset Management LLC ("HKAM") until his passing on April 7, 2026. On April 24, 2026, Eric Sites, who serves as a Managing Director of HKAM, was appointed to the Issuer's Board of Directors. Mr. Sites does not exercise investment discretion on behalf of HKAM with respect to the securities of the Issuer and is not deemed to beneficially own the securities reported herein. The extent of Mr. Sites' pecuniary interest in the securities of the Issuer are reported separately in his own filings. /s/ Jay Kesslen, attorney-in-fact 2026-05-21