Amazon's $600B Revenue Dwarfs Rivals — Why Ackman Picks It as Best AI Buy

For concentrated portfolio managers like Bill Ackman, every bet counts. His Pershing Square, holding only 8–12 stocks, has pivoted decisively into AI megacaps, swapping Alphabet for Microsoft in early 2026 and now signaling Amazon as the best value among the trio. With Amazon’s revenue eclipsing Microsoft and Meta combined and its AI chip business quietly becoming one of the world’s largest, this is a high-conviction play that could reshape how value investors approach big tech.

Billionaire hedge fund manager Bill Ackman, renowned for his concentrated bets through Pershing Square Capital Management, has steadily reshaped his portfolio around artificial intelligence. In the past year, the fund has initiated new positions in Amazon (AMZN), Microsoft (MSFT), and Meta Platforms (META), while exiting a long-held stake in Alphabet (GOOGL) in the first quarter of 2026. Ackman’s rationale for the Alphabet sale was blunt: he needed capital to buy Microsoft, which he deemed a more compelling opportunity. Now, with all three AI-facing giants in the portfolio, Ackman’s team has signaled that Amazon is the best buy of the bunch as of August 2026. This conviction rests on a powerful combination of scale, accelerating growth, and relative undervaluation.

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Billionaire hedge fund manager Bill Ackman, renowned for his concentrated bets through Pershing Square Capital Management, has steadily reshaped his portfolio around artificial intelligence.

Amazon’s sheer size is difficult to overstate. It is the world’s largest company by revenue—its trailing 12-month top line dwarfs Microsoft and Meta combined—yet it continues to expand at rates typically seen in smaller, hyper-growth enterprises. In its most recent quarter, Amazon posted double-digit revenue growth, powered in large part by its cloud division, Amazon Web Services. AWS is not only the global leader in cloud infrastructure but is also delivering accelerating sales growth—a dynamic that echoes the period when AWS was half its current revenue base. At the same time, Amazon’s emerging AI chip business has quietly become one of the three largest semiconductor operations on the planet, providing a self-reinforcing moat as enterprises build out AI workloads on AWS’s custom silicon.

Microsoft, by contrast, is embedding AI into its vast Office and enterprise software suite through Copilot, while Meta has deployed its large language model Llama to transform advertising across its social media empire. Both are formidable, but Amazon’s AI offensive is uniquely diversified: it sells AI infrastructure to customers via AWS, develops proprietary AI chips that reduce its own costs, and uses AI internally to optimize everything from routing packages to predicting demand. Pershing Square’s analysis further suggests that Amazon’s retail business—long criticized for thin margins—could nearly double its profitability as supply chain efficiencies and automation take hold. This provides a tangible earnings growth catalyst that may not be fully priced in.