Amazon.com Inc. shares fell roughly 7% in after-hours and pre-market trading after the company’s closely watched cloud unit disappointed investors, outweighing better-than-expected second-quarter results. The world’s largest online retailer reported revenue of $167.7 billion, a 13% increase year on year, and earnings of $1.68 a share, both ahead of Wall Street estimates. Yet Amazon Web Services, which typically supplies the bulk of operating profit, grew revenue 17.5% to $30.9 billion—slower than recent gains at Microsoft Azure and Google Cloud—and its operating margin narrowed to 32.9% from 35.5% a year earlier. Chief Executive Officer Andy Jassy said on a call that demand for generative artificial-intelligence services remains strong but conceded that competition has intensified. AWS still accounts for about 60% of Amazon’s total operating income. Investors were further unsettled by guidance that implied softer profitability. Amazon projected third-quarter net sales of $174 billion to $179.5 billion, slightly above analyst forecasts, but put operating income at $15.5 billion to $20.5 billion, with the lower end below consensus. The company also said capital expenditures could reach about $118 billion this year as it expands data-center capacity for AI workloads. Management cited tariffs, geopolitical tensions and interest-rate moves as sources of uncertainty heading into 2025, tempering optimism that Amazon’s core e-commerce and advertising businesses can maintain recent momentum.