US Stock Market Today (Dec. 19, 2025): S&P 500 and Nasdaq Climb on AI Rebound, Nike Slides, and “Triple Witching” Fuels Volatility
Semiconductor stocks led U.S. markets higher early Friday, with the SMH ETF up 2.9% and Nvidia and Micron gaining 3.6% and 6.7% respectively by early afternoon. The S&P 500 rose about 0.6%, Nasdaq 1.0%, and Dow 0.4%. Oracle and Carnival each jumped over 8%. Nike’s sharp drop weighed on the Dow during volatile “triple witching” trading.