S&P 500 logs biggest weekly drop since 2025 on AI trade worries

US stocks posted their biggest weekly loss since April 2025, with the S&P 500 falling 2.7%, driven by concerns over the artificial intelligence trade following a Democratic sweep in the US midterm elections. The Nasdaq 100 suffered its largest one-day rout since the Covid pandemic on Thursday, as anxiety grew over potential regulatory shifts that could curb growth for chipmakers and data center suppliers. Friday's modest gains failed to recover the losses, with the VIX volatility index rising the most since April 2025. The selloff was amplified by systematic trading strategies, and the Nasdaq 100 broke below its 200-day moving average for the deepest initial breach since 1985. Anthropic PBC's IPO plans faced uncertainty, while a stronger-than-expected October jobs report bolstered the case for a Federal Reserve rate hike.