US stock futures diverged in premarket trading on Thursday as Alphabet's Q3 earnings sparked a sell-off in the stock and AI jitters returned to markets, dragging on the tech-heavy indexes.

Futures on the Dow Jones Industrial Average ( YM=F ) fell below the flatline. Those on the S&P 500 ( ES=F ) slid 0.2%, while contracts for the Nasdaq-100 ( NQ=F ) fell 1%.

Tech stocks snapped a positive run this week as investors digested the Fed's rate pause on Wednesday and earnings from Microsoft (MSFT) and Alphabet (GOOG, GOOGL). Microsoft beat analyst expectations on the top and bottom lines, while Alphabet sales came up short. Although Google posted cloud growth of 103%, concerns about its free cash flow and AI return on investment were the albatross on the company's quarter.

A sell-off in AI names spread to Asian markets as South Korea's Kospi (^KS11) index declined. The iShares Semiconductor Index ETF (SOXX) also skidded after hours as Nvidia (NVDA), AMD (AMD), Micron (MU), and other chip stocks fell.

Markets will get another dose of hyperscaler earnings after the bell on Thursday when Amazon (AMZN) reports results. Several other big corporations, including Eli Lilly ( LLY ), Mastercard ( MA ), Intel ( INTC ), Caterpillar ( CAT ), and Anheuser-Busch InBev ( BUD ), will also provide insight into the AI trade and other facets of the economy.

A day after the Fed's interest rate decision, investors will also be treated to inflation data by way of the Personal Consumption Expenditures (PCE) index, which is expected to rise 3.1% on a core basis.