Underwriters Exercise Full Option to Purchase Additional Shares

PRINCETON, N.J. and MIAMI, Dec. 16, 2025 /PRNewswire/ -- Miami International Holdings, Inc. ("MIAX" or the "Company") (NYSE:MIAX), a technology-driven leader in building and operating regulated financial markets across multiple asset classes, today announced the closing of a secondary public offering of 7,762,500 shares of its common stock, which included 1,012,500 shares sold pursuant to the underwriters' exercise in full of its option to purchase additional shares, at a price to the public of $41.00 per share (the "Offering"). The Offering consisted entirely of secondary shares including shares issued upon the exercise of warrants sold by certain selling stockholders of MIAX.

The Company did not sell any shares of common stock in the Offering and did not receive any proceeds from the Offering.

J.P. Morgan, Morgan Stanley and Piper Sandler acted as lead joint bookrunning managers for the offering. Raymond James, Rosenblatt, William Blair, and Keefe, Bruyette & Woods, A Stifel Company, acted as joint bookrunning managers.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission ("SEC") and was declared effective on December 11, 2025. The Offering was made only by means of a prospectus. Copies of the final prospectus relating to the Offering may be obtained for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, copies of the prospectus may be obtained from: J.P. Morgan Securities LLC, Attention: c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or by email at prospectus-eq_fi@jpmchase.com and postsalemanualrequests@broadridge.com; Morgan Stanley & Co. LLC, Attention: Prospectus Department, 180 Varick Street, 2nd Floor, New York, NY 10014; or Piper Sandler & Co. at, 350 North 5th Street, Suite 1000, Minneapolis, MN 55401, Attention: Prospectus Department, by telephone at (800) 747-3924, or by email at prospectus@psc.com.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About MIAX

Miami International Holdings, Inc. (NYSE:MIAX) is a technology-driven leader in building and operating regulated financial markets across multiple asset classes and geographies. MIAX operates nine exchanges across options, futures, equities and international markets including MIAX^® Options, MIAX Pearl^®, MIAX Emerald^®, MIAX Sapphire^®, MIAX Pearl Equities™, MIAX Futures™, MIAXdx™, The Bermuda Stock Exchange (BSX) and The International Stock Exchange (TISE). MIAX also owns Dorman Trading, a full-service Futures Commission Merchant.

Disclaimer and Cautionary Note Regarding Forward-Looking Statements

This press release may contain forward-looking statements, including forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements describe future expectations, plans, results, or strategies and are generally preceded by words such as "may," "future," "plan" or "planned," "will" or "should," "expected," "anticipates," "draft," "eventually" or "projected." You are cautioned that such statements are based on management's current expectations and are subject to a multitude of risks and uncertainties that could cause future circumstances, events, or results to differ materially from those projected in the forward-looking statements, including the risks that actual results may differ materially from those projected in the forward-looking statements. Additional risks and uncertainties that may cause actual results to differ materially include the risks and uncertainties listed in Miami International Holdings, Inc.'s (together with its subsidiaries, the Company) public filings with the Securities and Exchange Commission. In providing forward-looking statements, the Company is not undertaking any duty or obligation to update these statements publicly as a result of new information, future events or otherwise.

All third-party trademarks (including logos and icons) referenced by the Company remain the property of their respective owners. Unless specifically identified as such, the Company's use of third-party trademarks does not indicate any relationship, sponsorship, or endorsement between the owners of these trademarks and the Company. Any references by the Company to third-party trademarks is to identify the corresponding third-party goods and/or services and shall be considered nominative fair use under the trademark law.

MIAX Contacts:

Investors

investor.relations@miaxglobal.com

Media

media@miaxglobal.com

View original content to download multimedia:https://www.prnewswire.com/news-releases/miami-international-holdings-announces-closing-of-secondary-public-offering-of-common-stock-302643444.html

SOURCE MIAX

Miami International Holdings Announces Closing of Secondary Public Offering of Common Stock