John Smollen - 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, 17:08:19 UTC
Next filing
19 Aug 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Smollen John EVP Traded Products & Relation C/O MIAMI INTERNATIONAL HOLDINGS, INC., 7 ROSZEL ROAD, SUITE 1A, PRINCETON /s/Alessandra Maria Corona Henriques, Attorney-in-Fact 13 Aug 2025 0002080703

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
holding MIAX Common Stock 2,226 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 91,666 Held by Quivetneck Capital LLC of which Mr. Smollen is a managing member F1
holding MIAX Nonvoting Common Stock 13 Aug 2025 Common Stock 65,947 Direct F2
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Series B Preferred Stock 24,999 $12.00 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 24,999 $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 7,757 $25.78 Direct F3
holding MIAX Incentive Stock Option (Right to Buy) 13 Aug 2025 Common Stock 5,041 $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 Series B Preferred Stock 125,001 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 75,001 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 104,167 $12.00 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 80,930 $15.22 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 29,743 $25.78 Direct F6
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 32,459 $19.84 Direct F7
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 37,500 $20.08 Direct F8
holding MIAX Nonqualified Stock Option (Right to Buy) 13 Aug 2025 Common Stock 16,072 $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 or Series B preferred stock, as applicable. On the closing date of the IPO, these will convert to the right to buy common stock instead of nonvoting common stock or Series B preferred stock, as applicable.
F4 1 of the shares subject to this incentive stock option is fully vested and the remaining 5,040 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 or Series B preferred stock, as applicable. On the closing date of the IPO, these will convert to the right to buy common stock instead of nonvoting common stock or Series B preferred stock, as applicable.
F7 24,999 of the shares subject to this nonqualified stock option are fully vested and the remaining 7,460 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 18,750 of the shares subject to this nonqualified stock option are fully vested and the remaining 18,750 will vest on June 30, 2026, subject to the reporting person's continued service to the Issuer or its subsidiaries through the applicable vesting date.
F9 8,334 of the shares subject to this nonqualified stock option will vest on June 16, 2026 and the remaining will vest as to 3,869 shares 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.

Remarks:

See Exhibit 24.1 - Power of Attorney