Quanta Services is trading at $531.18, with a +4.35% pre-market change after two sharp declines amid data-center rule concerns. - The broader sell-off reflected fears of tighter AI regulation and delayed infrastructure projects, pressuring AI-power contractors and peers; the market snapshot is mixed, not broadly risk-on. - Quanta Services reported strong third-quarter results and raised its 2026 outlook on October 29; no new company-specific announcement explaining the November 6 pre-market move was found.