Eric Sites - 15 Jun 2026 Form 4 Insider Report for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX)

Reporting relationship: Director
Issuer ticker: MIAX
Reported as of: 15 Jun 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 17 Jun 2026, 15:19:32 UTC
Prior SEC filing: 28 Apr 2026
Source filing: View source filing
Reporting owner signature: /s/ Jay Kesslen, attorney-in-fact

Key filing fact

Eric Sites filed Form 4 for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) on 17 Jun 2026.

Key facts

This page summarizes Eric Sites's Form 4 filing for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX).
2 reported transactions and 3 derivative rows are listed below.
Accepted by SEC: 17 Jun 2026, 15:19.

Change

Previous filing in this sequence was filed on 28 Apr 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001769842 Primary reporting owner

Sites Eric

Relationship: Director
Address: 470 PARK AVE S, 8TH FLOOR SOUTH, NEW YORK
Signature: /s/ Jay Kesslen, attorney-in-fact
Signature date: 17 Jun 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MIAX transaction

Common Stock

Award

Transaction value
Shares: +714
Change %
Price: $0.000000^*
Shares after: 714
Date: 15 Jun 2026
Ownership: Direct
Footnotes: F1

MIAX transaction

Common Stock

Award

Transaction value
Shares: +4,970
Change %: +696%
Price: $0.000000^*
Shares after: 5,684
Date: 16 Jun 2026
Ownership: Direct
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

MIAX holding Derivative

Nonqualified Stock Option (Right to Buy)

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 0
Date: 15 Jun 2026
Ownership: Direct
Underlying class: Miami International Holdings Inc
Underlying amount: 7,500
Exercise price: $16.14
Footnotes: F3

MIAX holding Derivative

Nonqualified Stock Option (Right to Buy)

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 0
Date: 15 Jun 2026
Ownership: Direct
Underlying class: Miami International Holdings Inc
Underlying amount: 9,554
Exercise price: $19.84
Footnotes: F3

MIAX holding Derivative

Nonqualified Stock Option (Right to Buy)

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 0
Date: 15 Jun 2026
Ownership: Direct
Underlying class: Miami International Holdings Inc
Underlying amount: 9,174
Exercise price: $20.00
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

The amount represents restricted stock units ("RSUs") that fully vested on the date of grant. Each RSU represents a right to receive one share of the Issuer's common stock.

Footnote F2

The amount represents RSUs that vest on the last business day immediately preceding the 2027 annual meeting of stockholders, subject to the Reporting Person's continued service to the Issuer through the vesting date.

Footnote F3

These options are fully vested.

SEC remarks

The Reporting Person, an employee of Horizon Kinetics Asset Management LLC and/or one of its affiliates (collectively, "HKAM"), is a member of the board of directors of the Issuer. HKAM has filed reports with the Securities and Exchange Commission reporting securities of the Issuer that it may be deemed to beneficially own. The Reporting Person does not exercise discretion of the securities of the Issuer and disclaims beneficial ownership that may be deemed to be beneficially owned by HKAM except to the extent of his pecuniary interest, if any.