ThZeal - The Zeal

SEC FORM 3 SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0104
Estimated average burden
hours per response:			0.5

1. Name and Address of Reporting Person^*

Gallagher Thomas P.

(Last)

(First)

(Middle)

C/O MIAMI INTERNATIONAL HOLDINGS, INC

7 ROSZEL ROAD, SUITE 1A

(Street)

PRINCETON

08540

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
08/13/2025

3. Issuer Name and Ticker or Trading Symbol
MIAMI INTERNATIONAL HOLDINGS, INC. [ MIAX ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	Chairman & CEO

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	1,904,599	I	By Gallagher Investments, LLC⁽¹⁾

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Series B Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	500	⁽²⁾	I	By Gallagher Investments, LLC⁽¹⁾
Nonvoting Common Stock	⁽³⁾	⁽³⁾	Common Stock	573,963	⁽³⁾	D
Nonvoting Common Stock	⁽³⁾	⁽³⁾	Common Stock	135,395	⁽³⁾	I	By Gallagher Investments, LLC⁽¹⁾
Incentive Stock Option (Right to Buy)	⁽⁴⁾	08/02/2026	Nonvoting Common Stock	24,999	$12	D
Incentive Stock Option (Right to Buy)	⁽⁴⁾	05/28/2028	Nonvoting Common Stock	16,666	$12	D
Incentive Stock Option (Right to Buy)	⁽⁴⁾	07/30/2029	Nonvoting Common Stock	8,333	$12	D
Incentive Stock Option (Right to Buy)	⁽⁴⁾	01/27/2031	Nonvoting Common Stock	13,140	$15.22	D
Incentive Stock Option (Right to Buy)	⁽⁵⁾	06/15/2035	Common Stock	13,392	$22.4	D
Nonqualified Stock Option (Right to Buy)	⁽⁶⁾	08/02/2026	Nonvoting Common Stock	350,001	$12	I	By Gallagher Investments, LLC⁽¹⁾
Nonqualified Stock Option (Right to Buy)	⁽⁶⁾	05/28/2028	Nonvoting Common Stock	283,334	$12	I	By Gallagher Investments, LLC⁽¹⁾
Nonqualified Stock Option (Right to Buy)	⁽⁶⁾	07/30/2029	Nonvoting Common Stock	241,667	$12	I	By Gallagher Investments, LLC⁽¹⁾
Nonqualified Stock Option (Right to Buy)	⁽⁶⁾	01/27/2031	Nonvoting Common Stock	286,860	$15.22	I	By Gallagher Investments, LLC⁽¹⁾
Nonqualified Stock Option (Right to Buy)	⁽⁶⁾	09/09/2031	Nonvoting Common Stock	375,000	$16.14	I	By Gallagher Investments, LLC⁽¹⁾
Nonqualified Stock Option (Right to Buy)	⁽⁷⁾	06/15/2035	Common Stock	97,858	$22.4	I	By Gallagher Investments, LLC⁽¹⁾

Explanation of Responses:

1. Mr. Gallagher maintains beneficial ownership, including dispositive and voting control, over Gallagher Investments, LLC.

2. 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.

3. The shares of nonvoting common stock are convertible on a one-for-one basis into shares of common stock commencing at any time. The nonvoting common stock has no expiration date.

4. The incentive stock options are fully vested. The options were granted initially as the right to buy nonvoting common stock. On the closing date of the IPO, these will convert to the right to buy common stock instead of nonvoting common stock.

5. 4,464 of the shares subject to this incentive stock option will vest on each of June 16, 2026, June 16, 2027 and June 16, 2028, subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.

6. The nonqualified stock options are fully vested. The options were granted initially as the right to buy nonvoting common stock. On the closing date of the IPO, these will convert to the right to buy common stock instead of nonvoting common stock.

7. 32,620 of the shares subject to this nonqualified stock option will vest on June 16, 2026, 32,619 will vest on June 16, 2027 and the remaining 32,619 will vest on June 16, 2028, subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.

Remarks:

See Exhibit 24.1 - Power of Attorney

	/s/Alessandra Maria Corona Henriques, Attorney-in-Fact	08/13/2025
	** Signature of Reporting Person	Date
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 5 (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.