# EDGAR Filing Document

**Accession Number:** 0001056823
**File Stem:** 0001437749-25-026579
**Filing Date:** 2025-8
**Character Count:** 8894
**Document Hash:** 648168549d76ddc165b1bc1d66075461
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001437749-25-026579.hdr.sgml**: 20250813

**ACCESSION NUMBER**: 0001437749-25-026579

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250813

**FILED AS OF DATE**: 20250813

**DATE AS OF CHANGE**: 20250813

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** HORIZON KINETICS ASSET MANAGEMENT LLC
- **CENTRAL INDEX KEY:** 0001056823

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42805
- **FILM NUMBER:** 251212958

**BUSINESS ADDRESS:**
- **STREET 1:** 470 PARK AVENUE SOUTH
- **STREET 2:** 4TH FLOOR SOUTH
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10016
- **BUSINESS PHONE:** 646-495-7347

**MAIL ADDRESS:**
- **STREET 1:** 470 PARK AVENUE SOUTH
- **STREET 2:** 4TH FLOOR SOUTH
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10016

**FORMER NAME:**
- **FORMER CONFORMED NAME:** HORIZON ASSET MANAGEMENT LLC
- **DATE OF NAME CHANGE:** 20130813

**FORMER NAME:**
- **FORMER CONFORMED NAME:** HORIZON ASSET MANAGEMENT INC/NY
- **DATE OF NAME CHANGE:** 19990319
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** STAHL MURRAY
- **CENTRAL INDEX KEY:** 0001207097

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42805
- **FILM NUMBER:** 251212959

**MAIL ADDRESS:**
- **STREET 1:** C/O HORIZON KINETICS LLC
- **STREET 2:** 470 PARK AVE S 8TH FL S
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10016
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MIAMI INTERNATIONAL HOLDINGS, INC.
- **CENTRAL INDEX KEY:** 0001438472
- **STANDARD INDUSTRIAL CLASSIFICATION:** SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
- **ORGANIZATION NAME:** 09 Crypto Assets
- **EIN:** 261482385
- **STATE OF INCORPORATION:** DE

**BUSINESS ADDRESS:**
- **STREET 1:** 7 ROSZEL ROAD
- **STREET 2:** FIFTH FLOOR, SUITE 1-A
- **CITY:** PRINCETON
- **STATE:** NJ
- **ZIP:** 08540
- **BUSINESS PHONE:** 609-897-7300

**MAIL ADDRESS:**
- **STREET 1:** 7 ROSZEL ROAD
- **STREET 2:** FIFTH FLOOR, SUITE 1-A
- **CITY:** PRINCETON
- **STATE:** NJ
- **ZIP:** 08540

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MIAMI INTERNATIONAL HOLDINGS INC
- **DATE OF NAME CHANGE:** 20080624

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>STAHL MURRAY<br><sub>(Last) (First) (Middle)</sub><br>470 PARK AVE S<br>8TH FLOOR SOUTH<br><sub>(Street)</sub><br>NEW YORK, NY 10016<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>MIAMI INTERNATIONAL HOLDINGS, INC. [ MIAX ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-08-13 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [ ] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>HORIZON KINETICS ASSET MANAGEMENT LLC<br><sub>(Last) (First) (Middle)</sub><br>470 PARK AVE S<br>8TH FLOOR SOUTH<br><sub>(Street)</sub><br>NEW YORK, NY 10016<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>MIAMI INTERNATIONAL HOLDINGS, INC. [ MIAX ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-08-13 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |
| Common Stock | 4196752 | I<sup>(1)(2)</sup> | Horizon Kinetics Asset Management LLC |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| OPTIONS | 2025-08-13 | 2031-05-31 | Miami International Holdings Inc | 2500 | 16.1400<sup>(3)</sup> | D |  |
| OPTIONS | 2025-08-13 | 2031-07-31 | Miami International Holdings Inc | 7500 | 16.1400<sup>(3)</sup> | D |  |
| OPTIONS | 2025-08-13 | 2032-06-30 | Miami International Holdings Inc | 10000 | 25.9800<sup>(3)</sup> | D |  |
| OPTIONS | 2025-08-13 | 2033-03-26 | Miami International Holdings Inc | 14331 | 19.8400<sup>(3)</sup> | D |  |
| Warrants | 2025-08-13 | 2026-11-15 | Miami International Holdings Inc | 24878 | 20.5000<sup>(1)(4)</sup> | I | Horizon Kinetics Asset Management LLC |
| Warrants | 2025-08-13 | 2027-02-05 | Miami International Holdings Inc | 27561 | 20.5000<sup>(1)(4)</sup> | I | Horizon Kinetics Asset Management LLC |
| Warrants | 2025-08-13 | 2026-04-08 | Miami International Holdings Inc | 21290 | 15.0000<sup>(1)(4)</sup> | I | Horizon Kinetics Asset Management LLC |
| Warrants | 2025-08-13 | 2026-10-17 | Miami International Holdings Inc | 38927 | 20.5000<sup>(1)(4)</sup> | I | Horizon Kinetics Asset Management LLC |

---

### Footnotes:

(1) Murray Stahl serves as Chairman, Chief Executive Officer, and Chief Investment Officer of Horizon Kinetics Asset Management LLC ("HKAM"), which manages funds and accounts (the "Managed Accounts") that hold securities of the Issuer.    Mr. Stahl does not exercise investment discretion with respect to the securities of the Issuer that are beneficially owned by the Managed Accounts. Mr. Stahl disclaims beneficial ownership over the securities reported, except to the extent of his pecuniary interest therein, if any.  The filing of this Form shall not be deemed an admission that the Mr. Stahl is the beneficial owner of such securities for purposes of Section 16 or any other purpose.

(2) Of the 4,196,752 shares owned; 5,000 shares are Series B, and 15,000 shares are Restricted and Exercised Non-Voting. The shares of Series B Preferred Stock are convertible on a one-for-one basis into shares of common stock commencing on the Company's initial public offering of its common stock ("IPO") effective date, which is August 13, 2025. The Series B Preferred Stock has no expiration date. The Restricted and Exercised Non-Voting shares are convertible on a one-for-one basis into shares of common stock commencing at any time. The Non-Voting common stock has no expiration date

(3) The options given to Mr. Stahl are fully vested. The options were granted initially as the right to buy nonvoting common stock. On the closing date of the Company's IPO of its common stock, these will convert to the right to buy common stock instead of nonvoting common stock.

(4) The warrants are currently vested and presently exercisable until the expiration date shown.

**Signature:** /s/ Jay Kesslen, attorney-in-fact  
**Date:** 2025-08-13

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**