Investing.com - U.S. stock index futures fell sharply on Tuesday, with technology shares once again leading losses amid a broader sell-off in artificial intelligence and semiconductor stocks.

By 07:56 ET, S&P 500 Futures had slid 1.2%, Nasdaq 100 Futures had tumbled 2.6%, and Dow Jones Futures had fallen 0.4%.

Artificial intelligence-linked stocks remained under pressure in premarket trading as investors continued to reassess valuations following a prolonged rally in the sector.

Here are some of the biggest premarket U.S. stock movers today:

• SpaceX shares remained volatile after plunging 16.4% in the previous session. The sell-off came after KeyBanc adopted a more cautious stance on the stock, citing valuation concerns following its sharp post-IPO rally. Shares later pared losses and were last up 1.4% in premarket trading.


• Nike slipped 1.4% after Evercore ISI downgraded the athletic apparel giant to In Line from Outperform and cut its price target to $46 from $57. The brokerage pointed to a slower-than-expected turnaround, ongoing wholesale channel challenges and weaker-than-anticipated fiscal 2027 revenue guidance.


• Zeta Global rose 5% after announcing a strategic partnership with Palantir Technologies aimed at building a unified data and artificial intelligence infrastructure for enterprise marketing. The agreement will see Zeta’s Data Cloud integrated with Palantir’s Foundry platform to enhance real-time decision-making capabilities for customers.