Stocks rebound after a dramatic week sparked by ongoing AI uncertainty

Market Performance - The S&P 500 rose 1.97%, marking its best day since May, while the Nasdaq Composite surged 2.18% on Friday, despite a sell-off in many tech stocks [1][3] - The Dow Jones Industrial Average reached 50,000 for the first time, although the S&P 500 is up less than 1% for the year, indicating a more nuanced market performance [7] Company Developments - Amazon's stock fell 5.58% after announcing a $200 billion spending plan, primarily for its Amazon Web Services division, leading to a 12% decline in its stock since Monday and a loss of over $310 billion in market value [1][2] - Microsoft and Meta also faced significant stock declines after announcing hundreds of billions in planned AI spending, contributing to a collective market value loss of nearly $1 trillion among Amazon, Microsoft, Meta, and Alphabet over five days [2][3] Sector Insights - Industrial and energy sectors performed well, with companies like Caterpillar benefiting from expected high demand for data centers [3][4] - Nvidia's shares rose nearly 8%, with the company now valued at over $4.5 trillion, as its CEO defended the sector's spending in response to high demand for AI applications [4] Investor Sentiment - The announcement by AI developer Anthropic about advanced AI capabilities triggered panic among investors in software and data analysis sectors, leading to heavy selling [5][6] - Small and medium stocks outperformed larger peers, with the Russell 2000 index soaring almost 4% [9]