Wall Street falls over 800 points as AI fears, tariff tensions and Supreme Court ruling shake markets

Market Overview - Wall Street stocks experienced a significant decline, with all three major U.S. stock indexes falling more than 1% due to fears surrounding artificial intelligence disruption and the fallout from a recent U.S. Supreme Court ruling [1] - Financial stocks dropped by 3.3%, while software-related firms saw a decline of 4.3% amid ongoing concerns about AI-related disruptions [2] Supreme Court Ruling Impact - The U.S. Supreme Court ruled 6-3 that former President Trump overstepped his authority by enacting tariffs under an economic emergency law, which has led to increased market volatility and uncertainty regarding trade policies [4] - Trump's response included a threat of a 15% temporary tariff on all imports, despite existing trade agreements with several U.S. partners [4] Investor Sentiment - Investor sentiment is characterized by a "sell first, assess later" approach, reflecting concerns about the costs and potential disruptions caused by AI technology [4] - The combination of geopolitical tensions, tariff uncertainties, and AI displacement is prompting a broad reassessment of risk among investors [6] Earnings Season Insights - The fourth-quarter earnings season is nearing completion, with 73% of companies that have reported beating expectations, leading to an aggregate year-on-year S&P 500 earnings growth forecast of 13.9%, up from an earlier forecast of 8.9% [9] - Notable companies expected to report earnings include Nvidia, Home Depot, Lowe's, Salesforce, and Universal Health Services [8] Sector Performance - Among the 11 major sectors of the S&P 500, financials suffered the largest percentage decline, while consumer staples showed resilience [10] - The healthcare index advanced by 1.2%, driven by a 4.9% gain in Eli Lilly following positive performance compared to a rival's obesity drug [10] Stock Movements - Domino's Pizza shares rose by 4.1% after reporting better-than-expected fourth-quarter same-store sales [10] - PayPal's stock jumped by 5.8% amid reports of takeover interest [11]