S&P 500 futures fall ahead of more U.S. economic data; South Korea's Kospi plunges 7%: Live updates

Nasdaq-100 futures fell sharply Thursday as worries over tech companies overspending on artificial intelligence intensified, while South Korea's Kospi plunged 7%, according to CNBC's live coverage. S&P 500 futures also slipped ahead of another round of U.S. economic data.

The setup is defensive. U.S. equities are coming off a losing session, and traders are now facing earnings reports and economic releases without the cushion of a prior rally. The drop in Nasdaq-100 futures points to the AI-spending concern as the main driver, with growth-heavy indexes absorbing the sharpest pressure.

The Kospi's 7% drop is the standout move. A decline of that size in a single session is a significant overseas risk-off signal landing right as U.S. futures turn lower. Interpretation: the simultaneous weakness in Seoul and in Nasdaq-100 futures suggests the AI-spending worry is being priced across global equity markets, not just in U.S. tech. That is analysis, not a confirmed causal link from the source.

Another interpretation: with S&P 500 futures weaker but the sharpest losses concentrated in the Nasdaq-100, the market appears to be differentiating between broad index exposure and AI-linked exposure. A pullback in the tech-heavy benchmark carries more weight when it follows a losing session.