The U.S. Securities and Exchange Commission (SEC) has unanimously approved new rules allowing stock exchanges to quote prices in increments of half a penny, aiming to enhance competition and reduce costs for investors. This significant reform, the first major update in nearly 20 years, is expected to narrow bid-ask spreads and improve pricing efficiency in the $55 trillion U.S. equity markets. The SEC also reduced access fee caps for exchanges, which may encourage better pricing practices. Although the changes have been welcomed for potentially balancing the competition between exchanges and dark markets, concerns have been raised by major market players like Citadel Securities regarding liquidity and market stability during volatile conditions. The new rules are set to take effect in November 2025, with the SEC looking to further overhaul market structures in the future.