Wall Street yo-yos as AI stocks swing from gains to losses

Wall Street's AI-driven rally stalled as major indices flickered between gains and losses. The S&P 500 slipped 0.2% after briefly climbing as much as 1% and then retreating to a 0.6% midmorning drop. The Dow Jones Industrial Average rose 162 points, or 0.3%, while the Nasdaq composite fell 0.6% as memory and chip names led the retreat. Micron Technology swung from a 4.2% morning gain to a 1.9% loss, a reversal after it jumped 9.9% the prior day and followed a 13.3% plunge two days earlier. Nuvalent jumped 38.8% after U.K.-based GlaxoSmithKline (GSK) agreed to acquire the biotech company for $10.6 billion. J.M. Smucker climbed 12.3% on stronger quarterly profit, while United Natural Foods dropped 13.5% on weaker revenue. Brent crude slid 3% to $91.40 a barrel after briefly topping $98, underscoring volatile energy markets that influence equities. The move in oil prices provided relief to stock sectors hit by elevated fuel costs, helping airline shares, including United up 3% and American up 3.9%. U.S. airlines spent more than $6 billion on jet fuel in April, up 78% year over year, a factor pressuring margins and fueling fare increases. Bond yields moved modestly lower, with the 10-year Treasury dipping to 4.54% from 4.56% on Monday, still well above pre-war levels near 3.97%. Investors awaited inflation data due later in the week, a development that could shape AI-risk sentiment and broader market rotations.