S&P 500, Nasdaq futures tumble ahead of earnings rush as valuation worries creep in
Tech led a sharp pullback in US stock futures on Tuesday as doubts about the AI-fueled rally crept in and investors waited for the next rush of quarterly earnings. S&P 500 futures (ES=F) sank 1.3%, while those on the tech-heavy Nasdaq 100 (NQ=F) tumbled 1.6%. Contracts on the Dow Jones Industrial Average (YM=F), which includes…