Welcome to our dedicated page for MIAMI INTERNATIONAL HOLDINGS SEC filings (Ticker: MIAX), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Our SEC filing database is enhanced with expert analysis from Rhea-AI, providing insights into the potential impact of each filing on MIAMI INTERNATIONAL HOLDINGS's stock performance. Each filing includes a concise AI-generated summary, sentiment and impact scores, and end-of-day stock performance data showing the actual market reaction. Navigate easily through different filing types including 10-K annual reports, 10-Q quarterly reports, 8-K current reports, proxy statements (DEF 14A), and Form 4 insider trading disclosures.
Designed for fundamental investors and regulatory compliance professionals, our page simplifies access to critical SEC filings. By combining real-time EDGAR feed updates, Rhea-AI's analytical insights, and historical stock performance data, we provide comprehensive visibility into MIAMI INTERNATIONAL HOLDINGS's regulatory disclosures and financial reporting.
MIAMI INTERNATIONAL HOLDINGS, INC. executive Douglas M. Schafer Jr., EVP and CIO, reported a Form 4 transaction involving 32,565 shares of common stock on February 18, 2026. The shares were surrendered back to the company to cover tax withholding on restricted stock awards, and the filing states this does not represent a market sale. After this tax-withholding disposition, he directly owns 396,681 shares.
MIAMI INTERNATIONAL HOLDINGS, INC. executive Edward Deitzel reported an administrative share transaction related to taxes. On February 18, 2026, he surrendered 6,035 shares of Common Stock at $40.89 per share to the company to satisfy tax withholding obligations tied to restricted stock awards.
A footnote explains this was a tax-withholding disposition and explicitly states it does not represent a sale by the reporting person. After this transaction, Deitzel directly owned 116,928 shares of Common Stock.
MIAMI INTERNATIONAL HOLDINGS, INC. executive Shelly Brown reported a Form 4 transaction involving the company’s common stock. On this date, 19,902 shares were surrendered to the company at $40.89 per share to satisfy tax withholding obligations tied to restricted stock awards, and Brown held 325,129 shares afterward.
MIAMI INTERNATIONAL HOLDINGS, INC. executive Douglas M. Schafer Jr., EVP and CIO, reported a tax-related share disposition. On February 10, 2026, 108,550 shares of common stock at $41.33 per share were surrendered to the company to cover tax withholding for restricted stock awards and are explicitly described as not a sale by the reporting person.
After this transaction, Schafer directly beneficially owned 429,246 common shares of the company.
Miami International Holdings, Inc. Chairman and CEO Thomas P. Gallagher, also a director, reported a Form 4 transaction involving company common stock. On February 10, 2026, 50,100 shares were disposed of at $41.33 per share in a transaction coded “F.”
According to the footnote, these shares were surrendered back to the company to satisfy tax withholding and remittance obligations related to the net settlement of restricted stock awards and do not represent an open-market sale. After this tax-withholding disposition, Gallagher directly beneficially owned 535,863 shares of common stock.
Miami International Holdings, Inc. reported that between December 15, 2025 and February 9, 2026 it issued a total of 3,973,663 shares of common stock. These shares were not registered under the Securities Act.
The issuances came from converting semi‑annually accrued but unpaid interest under a promissory note with a principal amount of $1,518,559 and from warrant exercises. Warrant holders provided $462,976 in cash and surrendered 72,135 existing shares through cashless exercises, increasing the overall share count while reducing some debt and bringing in cash.
Miami International Holdings, Inc. reported that it has closed the previously announced transaction to sell 90% of the issued and outstanding equity of MIAX Derivatives Exchange (MIAXdx), a wholly owned subsidiary, to a joint venture established by Robinhood Markets, Inc. in partnership with Susquehanna International Group. The Company has retained the remaining 10% equity interest in MIAXdx, so it continues to participate in the derivatives exchange while transferring majority ownership to the joint venture.
The transaction was effective as of January 20, 2026, and Miami International Holdings issued a press release on January 21, 2026, providing further details. That press release is included as Exhibit 99.1 to this report.
Miami International Holdings, Inc. chairman and CEO reported a transfer of shares to a family member. On 12/23/2025, he made a bona fide gift of 2,000 shares of common stock to his son. The shares given are subject to a lock-up agreement that he entered into on December 11, 2025, and the son has agreed to be bound by that agreement.
After this gift, he beneficially owns 585,963 shares of Miami International Holdings common stock. This total includes 12,000 shares held jointly with his spouse with right of survival. The transaction is reported as a gift, so no price is associated with the transfer.
Miami International Holdings, Inc. executive leadership reported multiple stock option exercises that increased direct ownership of the company’s common stock. The reporting person is an officer serving as EVP and Chief Strategy Officer.
On 12/16/2025, the officer exercised incentive stock options at an exercise price of $12 per share in three separate transactions for 16,666, 8,333, and 8,333 shares of common stock. Following these transactions, the officer beneficially owned 345,031 shares of common stock directly. The derivative securities table shows the related incentive stock option positions reduced to 0 derivative securities beneficially owned after the exercises, and the options are described as fully vested.
Miami International Holdings, Inc. reported that its EVP and CFO completed several incentive stock option exercises in company stock. On December 16, 2025, the executive exercised options to acquire 22,221 common shares at $13.50, 6,195 shares at $16.14, and 5,040 shares at $19.84.
After these transactions, the executive directly beneficially owned 127,612 shares of common stock. The filing also shows an incentive stock option with an exercise price of $19.84 for 5,040 shares expiring on March 28, 2033, and notes that 5,040 additional shares subject to this option are scheduled to vest on March 29, 2026, if the executive continues in service with the company or its subsidiaries.