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. (MIAX) reported insider transactions by Chairman & CEO Thomas P. Gallagher, effected through Gallagher Investments, LLC. On August 19, 2026, the entity sold 149,700 shares of common stock at a weighted average price of $41.13 per share under a previously adopted Rule 10b5-1 Plan. On August 18, 2026, 150,300 shares were surrendered to the company to satisfy tax withholding obligations upon net settlement of restricted stock awards, which is disclosed as not representing a market sale. Gallagher is stated to maintain beneficial ownership, including voting and dispositive control, over Gallagher Investments, LLC.
MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) reported an insider equity-tax event by executive officer Barbara J. Comly (EVP, GC & Corporate Secretary). On 2026-08-18, 43,420 shares of common stock at $42.41 per share were surrendered to the company to satisfy tax withholding on restricted stock awards, leaving her with 839,564 shares held directly; this was not an open-market sale.
MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) received a notice that Gallagher Investments LLC intends to sell up to 149,700 shares of common stock under Rule 144. The proposed sale is to be executed through Morgan Stanley Smith Barney LLC, with the common stock listed on the NYSE.
Gallagher Investments LLC previously executed multiple Rule 10b5-1 plan sales of MIAX common stock over the past three months, each with specified share amounts and aggregate dollar values.
MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) director Cynthia Schwarzkopf reported an option exercise-and-sale sequence involving 5,000 shares. She exercised 5,000 stock options at an exercise price of $12.00 per share, then sold 5,000 common shares at a weighted average price of $42.85 per share in trades ranging from $42.54–$43.33. Following the exercise, she held 11,916 stock options directly, and these transactions were effected under a previously established Rule 10b5-1 Plan adopted on March 12, 2026.
MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) reported that EVP and CFO Lance Emmons sold 35,000 shares of common stock on 2026-08-17 in an open-market transaction at a weighted average price of $42.83 per share. After this sale, he directly holds 86,538 shares. The sale was executed under a previously established Rule 10b5-1 trading plan adopted on December 17, 2025, and was completed in multiple trades at prices ranging from $42.23 to $43.54.
MIAX filed to permit the resale of 35,000 shares of its common stock through J.P. Morgan Securities LLC at 270 Park Avenue, New York. The filing lists an aggregate market value of about $1,523,200 and a CUSIP-related value reference of 99,230,898, with an indicative date of 08/17/2026 on the NYSE. The shares relate to previously granted equity compensation, including vested restricted stock awards from 2024 and 2025.
T. Rowe Price Investment Management, Inc., a Maryland corporation, filed a Schedule 13G reporting a significant position in Miami International Holdings common stock. The firm reports beneficial ownership of 5,032,970 shares, representing 5.3% of the class.
T. Rowe Price Investment Management reports sole voting power5,019,927 shares and sole dispositive power5,032,970 shares, with no shared voting or dispositive power. The firm expressly states that this filing should not be construed as an admission that it is the beneficial owner of these securities and that such beneficial ownership is denied.
Miami International Holdings, operator of options, equities, futures and international exchanges, reported strong growth for the three months ended June 30, 2026. Total revenues were 387,629 (dollars in thousands), up from 327,784, with revenues less cost of revenues rising to 141,113 from 104,662. Operating income was 27,797, roughly flat year over year, but net income increased to 44,208 and diluted EPS to 0.40.
For the first half of 2026, net income jumped to 214,432 (thousands) and diluted EPS to 1.95, compared with 2,107 and 0.03 a year earlier. Drivers included higher segment revenues, a 50,570 gain on the sale of 90% of MIAXdx to a Robinhood–SIG joint venture and an 85,603 income tax benefit, partly offset by a 30,000 litigation settlement with Nasdaq.
Cash, cash equivalents, segregated cash and restricted cash reached 804,289 at June 30, 2026, while total stockholders’ equity rose to 1,150,301. Debt consisted mainly of a 1,514 notes payable balance. Net cash provided by operating activities was 183,642 for the half year, and total cash and related balances increased by 246,705.
Miami International Holdings director Kurt M. Eckert exercised stock options for 1,063 shares of Common Stock at $12.00 per share on August 4, 2026, then sold 1,063 shares at a weighted average price of $45.80 per share. The options were fully vested and this grant was exhausted, with transactions effected under a Rule 10b5-1 Plan adopted on December 18, 2025.
Miami International Holdings, Inc. director Teekell Judson Gray reported selling 3,000 shares of Common Stock on August 4, 2026 at a weighted average price of $45.79 per share. Following this sale, he directly holds 72,251 shares. The transaction, executed in multiple trades between $45.13 and $46.56, was carried out under a previously established Rule 10b5-1 trading plan adopted on December 17, 2025.