IEXs

IEXs refers to a family of equity trading venues, most notably the Investors Exchange (IEX), and to the class of market operators that share a focus on reducing advantages created by speed in modern trading. IEXs are positioned as alternatives to traditional stock exchanges by emphasizing protections against latency arbitrage and aiming to provide fairer access for investors.

The Investors Exchange, founded in the early 2010s in the United States, sought to rethink market structure by introducing features designed to level the playing field for slower traders. In 2016, IEX received approval from the U.S. Securities and Exchange Commission to operate as a national securities exchange. The platform is known for a deliberate, uniform delay on incoming order messages, often described as a speed bump, which slows orders by about 350 microseconds. Proponents argue this design mitigates the speed advantage held by high-frequency traders, while critics contend it can affect liquidity and execution costs.

Market structure on IEXs typically centers on standard equity securities trading under regulatory oversight, with access rules, trading rules, and reporting practices aligned with U.S. securities laws. IEXs operate within the broader framework of Regulation NMS and participate in market data and surveillance systems overseen by the SEC and FINRA. The approach of IEXs has influenced discussions about fairness, liquidity provision, and the role of latency in modern markets, contributing to ongoing debates about optimal market design. See also stock exchanges, market microstructure, and high-frequency trading.