Shelly Brown - 13 Aug 2025 Form 3 Insider Report for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX)

Signature
/s/Alessandra Maria Corona Henriques, Attorney-in-Fact
Issuer symbol
MIAX
Transactions as of
13 Aug 2025
Net transactions value
$0
Form type
3
Filing time
13 Aug 2025, 17:09:36 UTC
Next filing
19 Aug 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Brown Shelly EVP, Strat. Planning & BD C/O MIAMI INTERNATIONAL HOLDINGS, INC., 7 ROSZEL ROAD, SUITE 1A, PRINCETON /s/Alessandra Maria Corona Henriques, Attorney-in-Fact 13 Aug 2025 0002080506

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
holding MIAX Common Stock 138,054 13 Aug 2025 Direct

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
holding MIAX Series B Preferred Stock 13 Aug 2025 Common Stock 500 Direct F1
holding MIAX Nonvoting Common Stock 13 Aug 2025 Common Stock 200,475 Direct F2
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 16,666 $12.00 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 8,333 $12.00 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 8,333 $12.00 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 8,333 $12.00 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 6,570 $15.22 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 6,195 $16.14 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 3,878 $25.78 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Common Stock 5,040 $19.84 Direct F4
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Common Stock 8,928 $22.40 Direct F5
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 65,334 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 41,667 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 91,667 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 141,667 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 143,430 $15.22 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 18,804 $16.14 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 46,121 $25.78 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 44,959 $19.84 Direct F7
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 75,000 $20.00 Direct F8
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 41,072 $22.40 Direct F9
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 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.
F2 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.
F3 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.
F4 All the shares subject to this incentive stock option will vest on March 29, 2026 subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.
F5 4,464 of the shares subject to this incentive stock option will vest on each of 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.
F6 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.
F7 33,333 of the shares subject to this nonqualified stock option are vested and the remaining 11,626 will vest on March 29, 2026 subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.
F8 25,000 of the shares subject to this nonqualified stock option are vested, 25,000 will vest on December 31, 2025 and the remaining 25,000 will vest on December 31, 2026, subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.
F9 16,667 of the shares subject to this nonqualified stock option will vest on June 16, 2026, 12,202 will vest on June 16, 2027 and the remaining 12,203 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