Shelly Brown of MIAMI INTERNATIONAL HOLDINGS (MIAX) exercises 30K options

Rhea-AI Filing Summary

MIAMI INTERNATIONAL HOLDINGS EVP and Chief Strategy Officer Shelly Brown exercised stock options to acquire additional common shares. On March 30, 2026, she exercised multiple fully vested Incentive Stock Options, converting rights to buy 30,016 shares of Common Stock at strike prices ranging from $12.00 to $25.78 per share.

A total of 1,809 Common Stock shares were surrendered at $37.50 per share to satisfy tax withholding and remittance obligations in connection with the net settlement of restricted stock awards, which the filing states does not represent a sale. Following these transactions, Brown directly owned 327,404 shares of Common Stock.

Insider Trade Summary

30,016 shares exercised/converted

Mixed 11 txns

Insider Brown Shelly

Role EVP, Chief Strategy Officer

Type	Security	Shares	Price	Value
Exercise	Incentive Stock Option (Right to Buy)	8,333	$0.00	--
Exercise	Incentive Stock Option (Right to Buy)	6,570	$0.00	--
Exercise	Incentive Stock Option (Right to Buy)	6,195	$0.00	--
Exercise	Incentive Stock Option (Right to Buy)	3,878	$0.00	--
Exercise	Incentive Stock Option (Right to Buy)	5,040	$0.00	--
Tax Withholding	Common Stock	1,809	$37.50	$68K
Exercise	Common Stock	8,333	$12.00	$100K
Exercise	Common Stock	6,570	$15.22	$100K
Exercise	Common Stock	6,195	$16.14	$100K
Exercise	Common Stock	3,878	$25.78	$100K
Exercise	Common Stock	5,040	$19.84	$100K

Holdings After Transaction: Incentive Stock Option (Right to Buy) — 0 shares (Direct); Common Stock — 297,388 shares (Direct)

Footnotes (1)

1. Represents shares that have been surrendered to the Company to satisfy tax withholding and remittance obligations in connection with the net settlement of restricted stock awards and does not represent a sale by the reporting person. The options are fully vested.

Key Figures

Options exercised: 30,016 shares Tax withholding shares: 1,809 shares Post-transaction holdings: 327,404 shares +2 more

5 metrics

Options exercised 30,016 shares Aggregate underlying Common Stock from option exercises on March 30, 2026

Tax withholding shares 1,809 shares Common Stock surrendered at $37.50 to satisfy tax obligations on March 30, 2026

Post-transaction holdings 327,404 shares Common Stock directly owned after transactions on March 30, 2026

Option strike prices $12.00–$25.78 per share Exercise prices of Incentive Stock Options converted into Common Stock

Largest single option lot 8,333 shares Incentive Stock Option exercised at $12.00 per share

Key Terms

Incentive Stock Option, Exercise or conversion of derivative security, tax withholding and remittance obligations, net settlement of restricted stock awards, +1 more

5 terms

Incentive Stock Option financial

"security_title: "Incentive Stock Option (Right to Buy)""

An incentive stock option is a type of employee benefit that gives a worker the right to buy company shares at a fixed price, with special tax advantages if the employee holds the shares for a required period. Think of it as a coupon to buy future shares at today’s price that can result in lower tax on the gain. Investors care because ISOs can dilute share count, align staff incentives with the stock price, and affect company compensation costs and the timing of potential share sales.

Exercise or conversion of derivative security financial

"transaction_code_description: "Exercise or conversion of derivative security""

tax withholding and remittance obligations financial

"Represents shares that have been surrendered to the Company to satisfy tax withholding and remittance obligations"

net settlement of restricted stock awards financial

"in connection with the net settlement of restricted stock awards and does not represent a sale"

fully vested financial

"The options are fully vested."

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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:			3235-0287
Estimated average burden
hours per response:			0.5

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

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Brown Shelly

(Last) (First) (Middle)

C/O MIAMI INTERNATIONAL HOLDINGS, INC.

7 ROSZEL ROAD, SUITE 1A

(Street)

PRINCETON NEW JERSEY 08540

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP, Chief Strategy Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/30/2026

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

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

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

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/30/2026		F		1,809(1)	D	$37.5	297,388	D
Common Stock	03/30/2026		M		8,333	A	$12	305,721	D
Common Stock	03/30/2026		M		6,570	A	$15.22	312,291	D
Common Stock	03/30/2026		M		6,195	A	$16.14	318,486	D
Common Stock	03/30/2026		M		3,878	A	$25.78	322,364	D
Common Stock	03/30/2026		M		5,040	A	$19.84	327,404	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Incentive Stock Option (Right to Buy)	$12	03/30/2026		M			8,333	(2)	07/31/2029	Common Stock	8,333	$0	0	D
Incentive Stock Option (Right to Buy)	$15.22	03/30/2026		M			6,570	(2)	11/30/2030	Common Stock	6,570	$0	0	D
Incentive Stock Option (Right to Buy)	$16.14	03/30/2026		M			6,195	(2)	09/09/2031	Common Stock	6,195	$0	0	D
Incentive Stock Option (Right to Buy)	$25.78	03/30/2026		M			3,878	(2)	03/09/2032	Common Stock	3,878	$0	0	D
Incentive Stock Option (Right to Buy)	$19.84	03/30/2026		M			5,040	(2)	03/28/2033	Common Stock	5,040	$0	0	D

Explanation of Responses:

1. Represents shares that have been surrendered to the Company to satisfy tax withholding and remittance obligations in connection with the net settlement of restricted stock awards and does not represent a sale by the reporting person.

2. The options are fully vested.

Remarks:

	/s/Alessandra Maria Corona Henriques, Attorney-in-Fact	04/01/2026
	** 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 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.
* Form 4: SEC 1474 (03-26)

FAQ

What did Shelly Brown report in this MIAX Form 4 filing?

Shelly Brown reported exercising multiple Incentive Stock Options to acquire MIAMI INTERNATIONAL HOLDINGS common shares. The transactions converted option rights into stock, increasing her direct ownership while also using some shares to cover tax obligations tied to restricted stock awards.

How many MIAX shares did Shelly Brown acquire through option exercises?

She exercised options relating to 30,016 shares of MIAMI INTERNATIONAL HOLDINGS common stock. These exercises converted Incentive Stock Options with various strike prices into directly held shares, reflecting compensation-related equity rather than open-market purchases or sales of existing holdings.

Were any of Shelly Brown’s MIAX shares actually sold in this Form 4?

No open-market sales were reported. The filing states 1,809 shares were surrendered to the company at $37.50 per share solely to satisfy tax withholding and remittance obligations from restricted stock awards, and explicitly notes this does not represent a sale by Brown.

What is Shelly Brown’s MIAX share ownership after these transactions?

After the reported transactions, Shelly Brown directly owned 327,404 shares of MIAMI INTERNATIONAL HOLDINGS common stock. This figure reflects the net result of her option exercises and the shares surrendered for tax withholding as of the March 30, 2026 transaction date.

What do the M and F transaction codes mean in this MIAX Form 4?

Code M indicates the exercise or conversion of derivative securities, here Incentive Stock Options converting into common stock. Code F indicates shares withheld or surrendered to pay exercise price or tax liabilities, which in this case covered tax obligations and was not treated as a market sale.

What are the strike prices of the MIAX options Shelly Brown exercised?

The Incentive Stock Options exercised had strike prices of $12.00, $15.22, $16.14, $19.84 and $25.78 per share. Exercising these options turned previously granted rights to buy MIAMI INTERNATIONAL HOLDINGS common stock into actual shares at those specified prices.