Key facts
- This page summarizes Murray Stahl's Form 4/A - Amendment filing for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX).
- 7 reported transactions and 8 derivative rows are listed below.
- Accepted by SEC: 06 Mar 2026, 16:12.
Murray Stahl - 02 Mar 2026 Form 4/A - Amendment Insider Report for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX)
- Reporting relationship
- Director
- Issuer ticker
- MIAX
- Reported as of
- 02 Mar 2026
- Net transaction value
- -$2,192,412
- SEC form
- 4/A - Amendment
- Accepted by SEC
- 06 Mar 2026, 16:12:14 UTC
- Original report date
- 04 Mar 2026
- Prior SEC filing
- 02 Mar 2026
- Next SEC filing
- 04 Mar 2026
- Source filing
- View source filing
- Reporting owner signature
- /s/Jay Kesslen, attorney-in-fact
Source evidence
Original filing metadata and source links for verification.
6 source fields
Reporting owner
1 detail
Key filing fact
Murray Stahl filed Form 4/A - Amendment for MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) on 06 Mar 2026.
Change
- Previous filing in this sequence was filed on 02 Mar 2026.
- Current net transaction value: -$2,192,412.
Research use
- This tells you what this filing adds before you inspect full transaction and derivative tables.
- You can trace every row back to the original SEC filing document.
Evidence
Filed on Form 4
View source filing
Ownership activity is grounded in SEC Form 4/A - Amendment disclosures.
Reporting Owners (2)
CIK 0001207097
Primary reporting owner
STAHL MURRAY
- Relationship
- Director
- Address
- 470 PARK AVE S, 8TH FLOOR SOUTH, NEW YORK
- Signature
- /s/Jay Kesslen, attorney-in-fact
- Signature date
- 06 Mar 2026
CIK 0001056823
HORIZON KINETICS ASSET MANAGEMENT LLC
- Relationship
- 10%+ Owner
- Address
- 470 PARK AVE S, 8TH FLOOR SOUTH, NEW YORK
- Signature
- /s/Jay Kesslen, attorney-in-fact
- Signature date
- 06 Mar 2026
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
MIAX
transaction
Common Stock
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- +21,290
- Change %
- +0.47%
- Price
- $15.00*
- Shares after
- 4,581,654
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Footnotes
- F1
MIAX
transaction
Common Stock
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- +91,366
- Change %
- +2%
- Price
- $20.50*
- Shares after
- 4,673,020
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Footnotes
- F1
MIAX
transaction
Common Stock
Sale
- Transaction value
- $2,192,412
- Shares
- -53,578
- Change %
- -1.1%
- Price
- $40.92
- Shares after
- 4,619,442
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Footnotes
- F1
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
MIAX
transaction
Derivative
Warrant (right to buy)
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- -21,290
- Change %
- -100%
- Price
- $0.000000*
- Shares after
- 0
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Underlying class
- Common Stock
- Underlying amount
- 21,290
- Exercise price
- $15.00
MIAX
transaction
Derivative
Warrant (right to buy)
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- -24,878
- Change %
- -100%
- Price
- $0.000000*
- Shares after
- 0
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Underlying class
- Common Stock
- Underlying amount
- 24,878
- Exercise price
- $20.50
MIAX
transaction
Derivative
Warrant (right to buy)
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- -27,561
- Change %
- -100%
- Price
- $0.000000*
- Shares after
- 0
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Underlying class
- Common Stock
- Underlying amount
- 27,561
- Exercise price
- $20.50
MIAX
transaction
Derivative
Warrant (right to buy)
Exercise of in-the-money or at-the-money derivative security
- Transaction value
- Shares
- -38,927
- Change %
- -100%
- Price
- $0.000000*
- Shares after
- 0
- Date
- 02 Mar 2026
- Ownership
- Horizon Kinetics Asset Management LLC
- Underlying class
- Common Stock
- Underlying amount
- 38,927
- Exercise price
- $20.50
MIAX
holding
Derivative
Options
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 7,500
- Date
- 02 Mar 2026
- Ownership
- Direct
- Underlying class
- Miami International Holdings Inc
- Underlying amount
- 7,500
- Exercise price
- $16.14
- Footnotes
- F2
MIAX
holding
Derivative
Options
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 10,000
- Date
- 02 Mar 2026
- Ownership
- Direct
- Underlying class
- Miami International Holdings Inc
- Underlying amount
- 10,000
- Exercise price
- $25.98
- Footnotes
- F2
MIAX
holding
Derivative
Options
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 14,331
- Date
- 02 Mar 2026
- Ownership
- Direct
- Underlying class
- Miami International Holdings Inc
- Underlying amount
- 14,331
- Exercise price
- $19.84
- Footnotes
- F2
MIAX
holding
Derivative
Options
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 2,500
- Date
- 02 Mar 2026
- Ownership
- Direct
- Underlying class
- Miami International Holdings Inc
- Underlying amount
- 2,500
- Exercise price
- $16.14
- Footnotes
- F2
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Explanation of responses 2 footnotes
Footnote F1
This amendment corrects a previous filing that inadvertently included shares that are not subject to reporting and also corrects the share totals. Horizon Kinetics Asset Management LLC (HKAM) exercised warrants to purchase 112,656 shares of common stock at the exercise prices noted. HKAM paid the exercise price on a cashless basis, resulting in the Issuer withholding 53,578 of the warrant shares to pay the exercise price and issuing to HKAM the remaining 59,078 shares.
Footnote F2
The Options given to Mr. Stahl are fully vested.