US stock exchanges to launch overnight trading sessions in December

US stock exchanges will launch overnight trading sessions starting December 6, extending market hours to nearly 24/5, with sessions from 9 p.m. to 4 a.m. New York time added by Nasdaq, NYSE Arca, 24X National Exchange, and Cboe EDGX. The expansion aims to attract foreign investors and compete with crypto and prediction markets, as overnight trading volume has surged 358% year-over-year, though it remains about 1% of total equity trading. Proponents cite improved global access, while skeptics warn of lower liquidity and wider bid-ask spreads during extended hours. Institutional investors remain cautious, with surveys showing reluctance due to operational risks and market quality concerns. Foreign investors currently drive 37% of overnight volume, and infrastructure providers like DTCC have already shifted to 24x5 clearing models to support the change.