Amazon (AMZN) is not a cheap stock at nearly 35x trailing earnings and about 31x forward earnings, but its AI investments are showing scale. Consolidated net sales grew 14% year-over-year to $213.4 billion in the Fourth Quarter of 2025. Amazon Web Services (AWS) revenues increased by 24% to $35.6 billion, compared to 20% in the prior quarter. AWS generated $12.5 billion in operating income in the Fourth Quarter, approximately half of total operating income. Over 2025, AWS represented approximately 18% of total sales but generated about 57% of total operating income. This year, investors focus on rapidly increasing AI demand, AWS expanding network capacity, and AI model developers like Anthropic strengthening AWS relationships. KeyBanc Analyst Justin Patterson sees a net benefit to AWS usage, illustrated by Anthropic's growth. Anthropic had $9 billion of recurring revenues at December 31, 2025, increasing to $30 billion at the beginning of April 2026. Approximately 60% of Anthropic's estimated cloud spending is through AWS. In March 2026, Anthropic released Claude Opus (4.7) and Claude Mythos, expected to increase AWS usage over the next few months.