AI warnings spark mixed moves in tech stocks as cybersecurity gains outpace semis

Tech shares slid after AI-safety warnings from Anthropic and OpenAI leaders raised questions about frontier AI, with the Nasdaq down about 0.8% and the Philadelphia Semiconductor Index off more than 4%; in contrast, cybersecurity names surged in premarket trading (Okta ~5%, CrowdStrike ~4.5%, Palo Alto Networks ~4.5%), with investors pricing in faster growth for security software as AI expands.