How Miami International Holdings (MIAX) is Redefining Derivatives Markets

The Q2 2026 investor letter from Langdon Partners revealed that Miami International Holdings (MIAX), a financial services company specializing in building and operating financial marketplaces in the United States, has been underperforming due to a 9.4% return, which is 7 percentage points below the MSCI World Small Cap Net Index's 17.0% gain.

The year-to-date performance of MIAX was also below long-term expectations, registering a -10.7% return compared to the index's 35.3%. The letter highlighted MIAX's electronic exchanges across various U.S. financial markets, emphasizing the company's potential in the derivatives market due to its existing position in U.S. listed options, proprietary technology infrastructure, and ability to introduce new products.

However, exchange operators face significant competitive, regulatory, and execution risks, and their economics can be affected by trading activity, pricing, market structure, and the actions of large incumbents. Despite these challenges, Langdon Partners initiated a position in MIAX during the second quarter, considering the company's potential in the derivatives market and its ability to generate attractive incremental margins with higher trading volumes.