The four largest AI cloud investors—Microsoft, Alphabet, Amazon, and Meta—are solid long-term buys because their core businesses generate enough profit to fund massive data center spending.

What happened: Microsoft, Alphabet, Amazon, and Meta are each spending hundreds of billions of dollars on data center capital expenditures this year. Microsoft's AI business has an annual run rate of $37 billion（約5.9兆円） growing at 123%, Azure grew revenue by 40%, AWS grew revenue 29% in Q1 (its best mark in nearly four years), and Google Cloud rose 63% in Q1.

Why it matters: Each of these four companies has a profitable core business—Microsoft's productivity software, Amazon's Web Services (AWS), Alphabet's search advertising, and Meta's social media advertising—that generates enough operating profit to self-fund their AI infrastructure spending. AWS accounted for 59% of Amazon's operating profits in Q1, showing the strength needed to sustain long-term AI investment.

What to watch: Meta is spending heavily on AI without yet showing a meaningful revenue stream from it, which makes it the cheapest of the four by valuation but also the riskiest. Meanwhile, Amazon is the most expensive because it has strong growth prospects and the most resilient core business.