MIAX (MIAX) EVP Shelly Brown sells 25,932 shares under 10b5-1 plan

Rhea-AI Filing Summary

MIAMI INTERNATIONAL HOLDINGS, INC. executive Shelly Brown, EVP and Chief Strategy Officer, sold 25,932 shares of common stock in an open-market transaction at a weighted average price of $39.33 per share. The shares were sold under a previously established Rule 10b5-1 trading plan adopted on December 22, 2025, indicating the sales were pre-scheduled. Following the transaction, Brown directly holds 299,197 shares. The trade was executed in multiple transactions during the day, at prices ranging from $38.98 to $39.80 per share.

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).

X

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)
03/23/2026

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	03/23/2026		S(1)		25,932	D	$39.33(2)	299,197	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

Explanation of Responses:

1. This transaction was effected pursuant to a previously established Rule 10b5-1 Plan adopted by the reporting person on December 22, 2025.

2. This transaction was executed in multiple trades throughout the day at prices ranging from $38.98 to $39.80. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the Securities and Exchange Commission staff, the issuer or a security holder of the issuer, full information regarding the number of shares and prices at which the transaction was effected.

Remarks:

	/s/Alessandra Maria Corona Henriques, Attorney-in-Fact	03/24/2026
	** 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 insider transaction did MIAX executive Shelly Brown report?

Shelly Brown reported an open-market sale of 25,932 MIAX common shares. The transaction used a weighted average price of $39.33 per share, with individual trades executed between $38.98 and $39.80 during the trading day.

Does Shelly Brown still hold MIAX shares after this Form 4 sale?

Yes, Shelly Brown continues to hold 299,197 MIAX common shares directly after the sale. This shows she retains a substantial equity position in the company even after the 25,932-share open-market transaction disclosed in this Form 4 filing.

Was Shelly Brown’s MIAX stock sale part of a Rule 10b5-1 trading plan?

Yes. The filing states the transaction was effected under a previously established Rule 10b5-1 plan. That plan was adopted on December 22, 2025, indicating the timing of this 25,932-share sale was pre-arranged rather than a discretionary same-day decision.

What price range did Shelly Brown receive for the MIAX shares sold?

The MIAX shares were sold in multiple trades at prices ranging from $38.98 to $39.80. The Form 4 reports a weighted average sale price of $39.33 per share for the 25,932 shares included in this transaction.

What role does Shelly Brown hold at MIAMI INTERNATIONAL HOLDINGS (MIAX)?

Shelly Brown is an officer of MIAMI INTERNATIONAL HOLDINGS, serving as Executive Vice President and Chief Strategy Officer. Her Form 4 filing reflects transactions in MIAX common stock made in her capacity as a corporate insider subject to SEC reporting rules.

How many MIAX shares did Shelly Brown sell according to the latest Form 4?

The latest Form 4 shows Shelly Brown sold 25,932 shares of MIAX common stock. These shares were sold in open-market transactions at a weighted average price of $39.33 per share, with execution prices spanning a narrow intraday range.