Anthropic's IPO filing shows 48% of revenue flows through rival cloud providers

Anthropic's IPO filing reveals that sales through rival cloud providers Amazon, Google, and Microsoft accounted for 48% of its revenue in the first half of 2026, up from 11% in 2023. The cloud providers sell access to Anthropic's Claude AI models, keeping a fee and passing the rest to the startup. This channel drove sales to $11.6 billion in the second quarter, but fees paid to partners surged to $3.2 billion, and the filing warns of risks from these companies acting as investors, competitors, and suppliers. Anthropic has committed to spending at least $269.5 billion with the three cloud giants through 2036, and it also relies on Broadcom and SpaceXAI for computing power. Amazon holds a roughly 9% economic stake, while Google holds at least 6.6%, with both having options to increase their positions.