On May 23, 2025, the U.S. stock market opened with mixed performance. The Cboe Volatility Index surged by 20.02%, indicating increased market uncertainty.

In sector performance, the U.S. semiconductor sector experienced a notable decline, with NVIDIA dropping 2.57% due to its collaboration with Innoscience and Navitas, which has sparked interest in the GaN market. Meanwhile, the U.S. gold stocks sector saw gains, with Gold Fields rising 4.02% and Harmony Gold Mining up 4.22%.

In individual stock news, Apple fell 3.10% following President Trump's announcement of a 25% tariff on foreign-made iPhones, which led to a significant drop in premarket trading. Microsoft saw a decline of 1.24% after the FTC dropped its case against Microsoft's acquisition of Activision Blizzard, citing resource allocation priorities. Amazon.com decreased by 2.42% as Bill Ackman's Pershing Square Hedge Fund invested in Amazon, influenced by the smaller-than-expected impact of tariffs. Alphabet fell 1.04% amid an antitrust investigation by the U.S. Department of Justice regarding its partnership with Character.AI. Meta Platforms, Inc. dropped 2.00% after a German court rejected a bid to block Meta from using user data for AI training.