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

Role
Director
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, 17:10:15 UTC
Previous filing
20 Jun 2025
Next filing
19 Aug 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Stahlin Paul Director C/O MIAMI INTERNATIONAL HOLDINGS, INC., 7 ROSZEL ROAD, SUITE 1A, PRINCETON /s/Alessandra Maria Corona Henriques, Attorney-in-Fact 13 Aug 2025 0001764337

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 10,000 Direct F1
holding MIAX Nonvoting Common Stock 13 Aug 2025 Common Stock 14,083 Direct F2
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 11,000 $12.00 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 18,000 $12.00 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 18,000 $12.00 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 18,000 $12.00 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 22,500 $14.00 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Nonvoting Common Stock 13,889 $16.14 Direct F3
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Common Stock 4,464 $25.98 Direct F4
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Common Stock 2,786 $19.84 Direct F4
holding MIAX Stock Option (Right to Buy) 13 Aug 2025 Common Stock 90 $20.60 Direct F4
* 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 and are held jointly with his spouse with right of survival. 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. Of his 14,083 shares of nonvoting common stock, (i) 10,000 are held in his individual name and (ii) 4,083 are held jointly with his spouse with right of survival. The nonvoting common stock has no expiration date.
F3 The 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 The options are fully vested.

Remarks:

See Exhibit 24.1 - Power of Attorney