Douglas M. Schafer Jr. - 15 Aug 2025 Form 4 Insider Report for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX)

Role
EVP and CIO
Signature
/s/Alessandra Maria Corona Henriques, Attorney-in-Fact
Issuer symbol
MIAX
Transactions as of
15 Aug 2025
Net transactions value
$0
Form type
4
Filing time
19 Aug 2025, 16:07:54 UTC
Previous filing
13 Aug 2025
Next filing
12 Feb 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Schafer Douglas M. JR EVP and CIO C/O MIAMI INTERNATIONAL HOLDINGS, INC., 7 ROSZEL ROAD, SUITE 1A, PRINCETON /s/Alessandra Maria Corona Henriques, Attorney-in-Fact 19 Aug 2025 0002079445

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MIAX Common Stock Conversion of derivative security +500 +0.09% 537,796 15 Aug 2025 Direct F1
transaction MIAX Common Stock Conversion of derivative security +387,296 +257% 537,796 15 Aug 2025 Direct F2

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
transaction MIAX Series B Preferred Stock Conversion of derivative security $0 -500 -100% $0.000000 0 15 Aug 2025 Common Stock 500 Direct F1
transaction MIAX Nonvoting Common Stock Conversion of derivative security $0 -387,296 -100% $0.000000 0 15 Aug 2025 Common Stock 387,296 Direct F2
transaction MIAX Incentive Stock Option (Right to Buy) Options Exercise $0 -16,666 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 16,666 $12.00 Direct F3, F4
transaction MIAX Incentive Stock Option (Right to Buy) Options Exercise $0 +16,666 $0.000000 16,666 15 Aug 2025 Common Stock 16,666 $12.00 Direct F3, F4
transaction MIAX Incentive Stock Option (Right to Buy) Options Exercise $0 -19,710 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 19,710 $15.22 Direct F3, F4
transaction MIAX Incentive Stock Option (Right to Buy) Options Exercise $0 +19,710 $0.000000 19,710 15 Aug 2025 Common Stock 19,710 $15.22 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 -150,000 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 150,000 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 +150,000 $0.000000 150,000 15 Aug 2025 Common Stock 150,000 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 -133,334 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 133,334 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 +133,334 $0.000000 133,334 15 Aug 2025 Common Stock 133,334 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 -200,000 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 200,000 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 +200,000 $0.000000 200,000 15 Aug 2025 Common Stock 200,000 $12.00 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 -130,290 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 130,290 $15.22 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 +130,290 $0.000000 130,290 15 Aug 2025 Common Stock 130,290 $15.22 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 -150,000 -100% $0.000000 0 15 Aug 2025 Nonvoting Common Stock 150,000 $16.14 Direct F3, F4
transaction MIAX Nonqualified Stock Option (Right to Buy) Options Exercise $0 +150,000 $0.000000 150,000 15 Aug 2025 Common Stock 150,000 $16.14 Direct F3, F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Represents 500 shares of Series B Preferred Stock, held jointly with his spouse with right of survivorship, that have been converted into shares of Common Stock on a one-for-one basis upon the closing of the Company's initial public offering ("IPO") and which have no expiration date.
F2 Represents 387,296 shares of Nonvoting Common Stock that have been converted into shares of Common Stock on a one-for-one basis upon the closing of the Company's IPO and which have no expiration date.
F3 The options were granted initially as the right to buy Nonvoting Common Stock. On the closing date of the IPO, these converted to the right to buy Common Stock instead of Nonvoting Common Stock, for the same price and under the same conditions.
F4 The options are fully vested.