MIAX (MIAX) EVP exercises 11K options, sells shares under 10b5-1 plan

Rhea-AI Filing Summary

MIAMI INTERNATIONAL HOLDINGS, INC. executive Edward Deitzel, EVP and CRO/CCO of MIAX Exchanges, reported an option exercise combined with a share sale. He exercised nonqualified stock options to acquire 11,000 shares of common stock at $12.00 per share, then sold 11,000 shares in open-market transactions at a weighted average price of $47.28 per share. After these transactions, he directly holds 116,221 shares of common stock and 18,333 nonqualified stock options expiring on May 17, 2028. The sale was carried out under a previously established Rule 10b5-1 trading plan adopted on December 30, 2025, indicating the trades were pre-scheduled.

Insider Trade Summary 10b5-1

Net Seller: 11,000 shares ($520,080)

Net Sell 3 txns

Insider Deitzel Edward

Role EVP, CRO, CCO MIAX Exchanges

Sold 11,000 shs ($520K)

Type	Security	Shares	Price	Value
Exercise	Nonqualified Stock Option (Right to Buy)	11,000	$0.00	--
Exercise	Common Stock	11,000	$12.00	$132K
Sale	Common Stock	11,000	$47.28	$520K

Holdings After Transaction: Nonqualified Stock Option (Right to Buy) — 18,333 shares (Direct, null); Common Stock — 127,221 shares (Direct, null)

Footnotes (1)

1. This transaction was effected pursuant to a previously established Rule 10b5-1 Plan adopted by the Reporting Person on December 30, 2025. This transaction was executed in multiple trades throughout the day at prices ranging from $46.92 to $47.65. 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. The options are fully vested.

Key Figures

Shares sold: 11,000 shares Weighted average sale price: $47.28 per share Options exercise price: $12.00 per share +4 more

7 metrics

Shares sold 11,000 shares Open-market sale of common stock on May 4, 2026

Weighted average sale price $47.28 per share Common stock sale on May 4, 2026

Options exercise price $12.00 per share Nonqualified stock option exercise for 11,000 shares

Shares held after transactions 116,221 shares Direct MIAX common stock ownership following Form 4 transactions

Options remaining 18,333 options Nonqualified stock options outstanding after exercise, expiring May 17, 2028

Rule 10b5-1 plan adoption date December 30, 2025 Date Deitzel adopted pre-arranged trading plan

Intraday sale price range $46.92–$47.65 per share Range for multiple trades comprising the 11,000-share sale

Key Terms

Rule 10b5-1 Plan, Nonqualified Stock Option (Right to Buy), weighted average sale price, open-market sale, +1 more

5 terms

Rule 10b5-1 Plan regulatory

"This transaction was effected pursuant to a previously established Rule 10b5-1 Plan adopted by the Reporting Person"

A Rule 10b5-1 plan is a prearranged, written schedule that lets corporate insiders buy or sell company stock at set times or amounts, even if they later learn material nonpublic information. Think of it like setting an automatic thermostat for trades: it creates a clear record that trades were planned in advance, reducing the risk of insider-trading accusations and helping investors trust that insider transactions are routine rather than based on secret information.

Nonqualified Stock Option (Right to Buy) financial

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

weighted average sale price financial

"The price reported above reflects the weighted average sale price."

open-market sale financial

"transaction_action: "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

derivative exercise/conversion financial

"transaction_action: "derivative exercise/conversion""

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).

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^*

Deitzel Edward

(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, CRO, CCO MIAX Exchanges

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/04/2026

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	05/04/2026		M(1)		11,000	A	$12	127,221	D
Common Stock	05/04/2026		S(1)		11,000	D	$47.28(2)	116,221	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
Nonqualified Stock Option (Right to Buy)	$12	05/04/2026		M(1)			11,000	(3)	05/17/2028	Common Stock	11,000	$0	18,333	D

Explanation of Responses:

1. This transaction was effected pursuant to a previously established Rule 10b5-1 Plan adopted by the Reporting Person on December 30, 2025.

2. This transaction was executed in multiple trades throughout the day at prices ranging from $46.92 to $47.65. 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.

3. The options are fully vested.

Remarks:

	/s/Alessandra Maria Corona Henriques, Attorney-in-Fact	05/05/2026
	** 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 MIAX executive Edward Deitzel do in this Form 4 filing?

Edward Deitzel exercised 11,000 stock options at $12.00 and sold 11,000 MIAX common shares at a weighted average price of $47.28. This combination converts option-based compensation into cash while leaving his common share holdings unchanged overall.

How many MIAX shares does Edward Deitzel own after these transactions?

After the reported transactions, Edward Deitzel directly holds 116,221 MIAX common shares. He also retains 18,333 nonqualified stock options expiring on May 17, 2028, showing he maintains a meaningful equity-linked position in the company.

At what prices did Edward Deitzel trade MIAX stock in this Form 4?

He exercised options to acquire 11,000 MIAX shares at $12.00 per share, then sold 11,000 shares at a weighted average price of $47.28. The sales occurred in multiple trades between $46.92 and $47.65 per share.

Was Edward Deitzel’s MIAX stock sale pre-planned under Rule 10b5-1?

Yes. The filing states the sale was executed under a previously established Rule 10b5-1 trading plan adopted on December 30, 2025. Such plans pre-schedule trades, indicating the sale timing reflects a prearranged program rather than an ad hoc decision.

What happens to Edward Deitzel’s MIAX options after this exercise and sale?

Following the exercise of 11,000 nonqualified stock options, Deitzel has 18,333 options remaining with an exercise price of $12.00 and expiration on May 17, 2028. The reported transactions reduce his outstanding options while keeping his share count steady.