On November 5, U.S. stocks opened mixed, with the Dow up 0.56%, the S&P 500 down 0.13%, and the Nasdaq down 0.8%. Market concerns over tighter U.S. regulation of AI and data centers weighed on tech stocks: Qualcomm fell 13%, AMD dropped 7%, Micron Technology declined 4.9%, Tesla fell 3.5%, and SpaceX dropped 4%. Qualcomm's steep decline stemmed from bearish fiscal 2026 Q4 earnings and guidance released on November 4: mobile chip revenue fell sharply year-over-year and missed expectations, with margins declining; the midpoint of fiscal 2027 Q1 Non-GAAP EPS guidance came in below expectations; Apple's in-house modem is eroding revenue, and the company expects the overall mobile phone market to be flat in 2027, with new business growth insufficient to offset the decline in its core business, prompting multiple institutions to cut their target prices.