# EDGAR Filing Document

**Accession Number:** 0001438472
**File Stem:** 0001438472-26-000025
**Filing Date:** 2026-3
**Character Count:** 24603
**Document Hash:** 3b61a0f47f5471a2f67257ed72ea7884
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001438472-26-000025.hdr.sgml**: 20260306

**ACCESSION NUMBER**: 0001438472-26-000025

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 15

**FILED AS OF DATE**: 20260306

**EFFECTIVENESS DATE**: 20260306

**FILER**: 

**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

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-294077
- **FILM NUMBER:** 26728479

**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

As filed with the Securities and Exchange Commission on March 5, 2026

**Registration No. 333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;** 

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549** 

**FORM S-8**

**REGISTRATION STATEMENT**

**UNDER**

**THE SECURITIES ACT OF 1933**

**MIAMI INTERNATIONAL HOLDINGS, INC.**

(Exact name of registrant as specified in its charter)

---

| | |
|:---|:---|
| **Delaware** | **26-1482385** |
| (State or other jurisdiction of<br>incorporation or organization) | (I.R.S. Employer<br>Identification No.) |
| **7 Roszel Road, Suite 1A**<br>**Princeton, New Jersey** <br>(Address of Principal Executive Offices) | **08540**<br>(Zip Code) |

---

**2022 Equity Incentive Plan**

(Full title of the plan)

**Thomas P. Gallagher**

**Chairman and Chief Executive Officer**

**Miami International Holdings, Inc.**

**7 Roszel Road, Suite 1A**

**Princeton, New Jersey 08540**

**(609) 897-7300**

(Name, address and telephone number, including area code, of agent for service)

Copy to:

---

| | | |
|:---|:---|:---|
| **Herbert F. Kozlov, Esq.**<br>**Danielle Carbone, Esq.**<br>**Reed Smith LLP**<br>**599 Lexington Avenue**<br>**New York, New York 10022**<br>**(212) 521-5400** | B**arbara Comly, Esq.**<br>**Executive Vice President, General**<br>**Counsel and Corporate Secretary**<br>**Miami International Holdings, Inc.**<br>**7 Roszel Road, Suite 1A**<br>**Princeton, New Jersey 08540**<br>**(609) 897-7300** | **Jeffrey G. Aromatorio, Esq.<br>Reed Smith LLP<br>225 Fifth Avenue<br>Pittsburgh, Pennsylvania 15222<br> (412) 288-3364** |

---

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

---

| | | | |
|:---|:---|:---|:---|
| Large Accelerated Filer | ☐ | Accelerated Filer | ☐ |
| Non-Accelerated Filer | ☒ | Smaller reporting company | ☐ |
| | | Emerging growth company | ☐ |

---

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

------

**REGISTRATION OF ADDITIONAL SECURITIES PURSUANT TO GENERAL INSTRUCTION E**

This Registration Statement on Form S-8 (this "Registration Statement") is being filed for the purpose of registering 4,276,814 additional shares of common stock, par value $0.001 per share, of Miami International Holdings, Inc. (the "Registrant") available for issuance under the Registrant's 2022 Equity Incentive Plan (the "2022 Plan") pursuant to the provision of the 2022 Plan providing for an annual automatic increase in the number of shares reserved for issuance under the 2022 Plan. The Registrant previously registered shares of its common stock for issuance under the 2022 Plan under a Registration Statement on Form S-8, filed with the Securities and Exchange Commission (the "SEC") on August 13, 2025 (File No. 333-289581) (the "Previous Registration Statement"). Pursuant to General Instruction E to Form S-8, the Registrant hereby incorporates by reference herein the contents of the Previous Registration Statement, and hereby deems the contents of the Previous Registration Statement to be a part of this Registration Statement, in each case except as supplemented, amended or superseded by the information set forth below herein.

**PART II**

**INFORMATION REQUIRED IN THE REGISTRATION STATEMENT**

**ITEM 3.**&nbsp;&nbsp;&nbsp;&nbsp;**INCORPORATION OF DOCUMENTS BY REFERENCE**

The following documents filed with the SEC by the Registrant are incorporated herein by reference.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)the Company's Annual Report on Form 10-K for the year ended December 31, 2025 as filed with the SEC on <u>[March](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000023/miax-20251231.htm)[6](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000023/miax-20251231.htm)[, 2026](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000023/miax-20251231.htm)</u>;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)the Company's Current Reports on Form 8-K as filed with the SEC on <u>[January 21, 2026](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000008/miax-20260120.htm)</u>, <u>[February 12, 2026](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000010/miax-20260209.htm)</u> <u>[February 20, 2026](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000012/miax-20260218.htm)</u> and <u>[March 2, 2026](https://www.sec.gov/ix?doc=/Archives/edgar/data/0001438472/000143847226000019/miax-20260225.htm)</u> (other than any portions thereof deemed furnished and not filed); and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3)The description of the Registrant's common stock which is contained in a registration statement on Form 8-A filed on <u>[August 13, 2025](https://www.sec.gov/Archives/edgar/data/1438472/000162828025040054/miamiinternationalinc-form.htm)</u> (File No. 001-42805) under the Exchange Act of 1934, as amended (the "Exchange Act"), including any amendments or reports filed for the purpose of updating such description, including Exhibit 4.7 to the Registrant's Annual Report on Form 10-K referred to in (1) above.

All documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment which indicates that all securities offered have been sold, or which deregisters all of the securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part hereof from the date of filing of such documents.

Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein, or in any other subsequently filed document which also is incorporated or deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Notwithstanding the foregoing, unless specifically stated to the contrary, none of the information disclosed by the Registrant under Items 2.02 or 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, that the Registrant may from time to time furnish to the Commission will be incorporated by reference into, or otherwise included in, this Registration Statement.

------

**ITEM 8.**&nbsp;&nbsp;&nbsp;&nbsp;**EXHIBITS**

The following exhibits are hereby filed as part of this Registration Statement:

---

| | |
|:---|:---|
| **Exhibit Number** | **Exhibit Description** |
| 4.1 | <u>[Amended and Restated Certificate of Incorporation, as currently in effect (incorporated herein by reference to Exhibit 3.1 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit31-sx1.htm)</u> |
| 4.2 | <u>[Amended and Restated By-Laws, as currently in effect (incorporated herein by reference to Exhibit 3.2 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit32-sx1.htm)</u> |
| 4.3 | <u>[Form of Voting Common Stock Certificate (incorporated herein by reference to Exhibit 4.1 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit41-sx1.htm)</u> |
| 5.1\* | <u>[Opinion of](mih-sx8opinion2026evergreen.htm)[Re](mih-sx8opinion2026evergreen.htm)[ed Smith LLP](mih-sx8opinion2026evergreen.htm)[.](mih-sx8opinion2026evergreen.htm)</u> |
| 23.1\* | <u>[Consent of Independent Registered Public Accounting Firm](s-8consent.htm)[.](s-8consent.htm)</u> |
| 23.2\* | <u>[Consent of](mih-sx8opinion2026evergreen.htm)[Reed Smith LLP](mih-sx8opinion2026evergreen.htm)[(reference is made to Exhibit 5.1).](mih-sx8opinion2026evergreen.htm)</u> |
| 24.1\* | <u>[Power of Attorney (reference is made to the signature page hereto).](#i537aa59350fc44ecb2e90db55f152e2d_1327)</u> |
| 99.1 | <u>[Miami International Holdings, Inc. 2022 Equity Incentive Plan (incorporated herein by reference to Exhibit 10.14 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit1014-sx1.htm)</u> |
| 99.2 | <u>[Form of Notice of Stock Option Grant and Stock Option Award Agreement pursuant to the Miami International Holdings, Inc. 2022 Equity Incentive Plan (incorporated herein by reference to Exhibit 10.15 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit1015-sx1.htm)</u> |
| 99.3 | <u>[Form of Restricted Stock Award Agreement pursuant to the Miami International Holdings, Inc. 2022 Equity Incentive Plan (incorporated herein by reference to Exhibit 10.16 to the Registrant's Registration Statement on Form S-1 (File No. 333-288767), filed with the SEC on July 18, 2025).](https://www.sec.gov/Archives/edgar/data/1438472/000162828025035343/exhibit1016-sx1.htm)</u> |
| 107\* | <u>[Filing Fee Table](exfilingfees.htm)[.](exfilingfees.htm)</u> |

---

\* Filed herewith.

------

**SIGNATURES**

Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Princeton, State of New Jersey on March 5, 2026.

---

| | |
|:---|:---|
| **MIAMI INTERNATIONAL HOLDINGS, INC.** | **MIAMI INTERNATIONAL HOLDINGS, INC.** |
| By: | /s/ Thomas P. Gallagher |
|  | Thomas P. Gallagher |
|  | Chairman and Chief Executive Officer |

---

------

**POWER OF ATTORNEY**

Each person whose signature appears below constitutes and appoints Thomas P. Gallagher and Barbara J. Comly, and each of them acting individually and without the other, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and re-substitution, for him or her and in his or her name, place, and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments, exhibits thereto and other documents in connection therewith) to this Registration Statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or either of them individually, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

------

Pursuant to the requirements of the Securities Act, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Thomas P. Gallagher | Chairman and Chief Executive Officer <br>(*Principal Executive Officer*) | March 5, 2026 |
| Thomas P. Gallagher | Chairman and Chief Executive Officer <br>(*Principal Executive Officer*) | March 5, 2026 |
| /s/ Lance Emmons | Executive Vice President and Chief Financial Officer <br>(*Principal Financial and Accounting Officer*) | March 5, 2026 |
| Lance Emmons | Executive Vice President and Chief Financial Officer <br>(*Principal Financial and Accounting Officer*) | March 5, 2026 |
| /s/ Talal Jassim Al-Bahar | Director | March 5, 2026 |
| Talal Jassim Al-Bahar | Director | March 5, 2026 |
| /s/ John Beckelman | Director | March 5, 2026 |
| John Beckelman | Director | March 5, 2026 |
| /s/ Lee Becker | Director | March 5, 2026 |
| Lee Becker | Director | March 5, 2026 |
| /s/ David Brown | Director | March 5, 2026 |
| David Brown | Director | March 5, 2026 |
| /s/ Kurt M. Eckert | Director | March 5, 2026 |
| Kurt M. Eckert | Director | March 5, 2026 |
| /s/ Kenneth W. Lozier | Director | March 5, 2026 |
| Kenneth W. Lozier | Director | March 5, 2026 |
| /s/ Mark I. Massad | Director | March 5, 2026 |
| Mark I. Massad | Director | March 5, 2026 |
| /s/ Lisa Moore | Director | March 5, 2026 |
| Lisa Moore | Director | March 5, 2026 |
| /s/ Mark F. Raymond | Director | March 5, 2026 |
| Mark F. Raymond | Director | March 5, 2026 |
| /s/ Cynthia Schwarzkopf | Director | March 5, 2026 |
| Cynthia Schwarzkopf | Director | March 5, 2026 |
| /s/ Murray Stahl | Director | March 5, 2026 |
| Murray Stahl | Director | March 5, 2026 |
| /s/ Paul V. Stahlin | Director | March 5, 2026 |
| Paul V. Stahlin | Director | March 5, 2026 |
| /s/ J. Gray Teekell | Director | March 5, 2026 |
| J. Gray Teekell | Director | March 5, 2026 |

---

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

---

| |
|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **MIAMI INTERNATIONAL HOLDINGS, INC.**  |

---

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Type**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Class Title**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Calculation Rule**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount Registered**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Proposed Maximum Offering Price Per Unit**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Maximum Aggregate Offering Price**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Rate**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount of Registration Fee**  |
| 1 | Equity | Common stock, $0.001 par value per share | Other | 4276814 | $41.63 | $178043766.82 | 0.0001381 | $24587.84 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $178043766.82  |  | $24587.84  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $24587.84  |

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Offering Note** <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>1</sup> 1a. Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall also cover any additional shares of Miami International Holdings, Inc. (the "Registrant") common stock that become issuable under the 2022 Equity Incentive Plan in respect of the securities identified in the above table by reason of any stock dividend, stock split, recapitalization, or other similar transaction effected without the Registrant's receipt of consideration that increases the number of the outstanding shares of the Registrant's common stock. 1b. Pursuant to Rules 457(c) and (h) under the Securities Act, the proposed maximum offering price per share and the proposed maximum aggregate offering price are estimated for the purpose of calculating the amount of the registration fee and are based on the average of the high and low sales price, $43.26 and $40.00, respectively, on March 2, 2026 (which is within five business days prior to the date of filing of this Registration Statement). 1c. The Registrant does not have any fee offsets.

---

| | |
|:---|:---|
| | |
| **Rule 457(p)** | **Rule 457(p)** |
| Fee Offset Claims | N/A |
| Fee Offset Sources | N/A |

---

## Exhibit 5.1

**Exhibit 5.1**

---

| | |
|:---|:---|
| ![image_0.jpg](image_0.jpg) | Reed Smith LLP<br>599 Lexington Avenue<br>New York, NY 10022-7650<br>+1 212 521 5400<br>Fax +1 212 521 5450<br>reedsmith.com |

---

March 5, 2026

7 Roszel Road, Suite 1A

Princeton, New Jersey

Ladies and Gentlemen:

We have acted as counsel to Miami International Holdings, Inc., a Delaware corporation (the "**Company**"), in connection with the Registration Statement on Form S-8 (the "**Registration Statement**") filed by the Company with the Securities and Exchange Commission (the "**Commission**") under the Securities Act of 1933, as amended (the "**Securities Act**"), relating to the offer and sale by the Company of up to 4,276,814 shares of common stock, par value $0.001 per share of the Company (the "**Shares**"), reserved for issuance under the 2022 Equity Incentive Plan (the "**Plan**"). This opinion letter is being furnished in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

We have reviewed originals or copies of the Registration Statement, the Amended and Restated Certificate of Incorporation and Amended and Restated By-Laws of the Company, as amended through the date hereof, and such other corporate records, agreements and documents of the Company, certificates or comparable documents of public officials and officers of the Company and have made such other investigations as we have deemed necessary as a basis for the opinion set forth below.

In rendering the opinion set forth below, we have assumed:

 a. the genuineness of all signatures;

 b. the legal capacity of natural persons;

 c. the authenticity of all documents submitted to us as originals;

 d. the conformity to original documents of all documents submitted to us as duplicates or conformed copies;

 e. as to matters of fact, the truthfulness of the representations made in certificates or comparable documents of public officials and officers of the Company;

 f. the board of directors of the Company or a duly constituted and acting committee of such board of directors will have taken all action necessary to set the public offering price of the Shares;

g. with respect to the issuance of the Shares, the amount of valid consideration paid in respect of such Shares will equal or exceed the par value of such Shares; and

h. that there are no agreements or understandings between or among the Company and any participants in the Plan that would expand, modify or otherwise affect the terms of the Plan or the respective rights or obligations of any participants thereunder.

------

We have not independently established the validity of the foregoing assumptions.

Based upon the foregoing, and subject to the qualifications, assumptions and limitations stated herein, we are of the opinion that, when the Shares are issued and sold by the Company in the manner contemplated in the Registration Statement against payment therefor in the circumstances contemplated by the Plan and assuming that the individual issuances, grants or awards under the Plan are duly authorized by all necessary corporate action of the Company and duly issued, granted or awarded and exercised and paid for, for consideration at least equal to the par value thereof, in accordance with the requirements of law and the Plan (and the agreements and awards either duly adopted thereunder and in accordance therewith), the offer and sale of the Shares shall have been duly authorized and, when and to the extent that the Shares are issued in accordance with the foregoing, the Shares will be validly issued, fully paid and nonassessable.

Our opinion is limited to the General Corporation Law of the State of Delaware and we do not express any opinion herein concerning any other law. This opinion letter speaks only as of its date.

We hereby consent to the filing of this opinion letter as Exhibit 5.1 to the Registration Statement and to the use of our name therein. In giving such consent, we do not hereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act, and the rules and regulations of the Commission promulgated thereunder.

Very truly yours,

/s/ Reed Smith LLP

REED SMITH LLP

## Exhibit 23.1

**Exhibit 23.1**

**Consent of Independent Registered Public Accounting Firm**

We consent to the use of our report dated March 5, 2026, with respect to the consolidated financial statements of Miami International Holdings, Inc., incorporated herein by reference.

/s/ KPMG LLP

New York, New York

March 5, 2026

<br>