Exclusive-Anthropic IPO prospectus lays bare deep dependence on Big Tech partners

Anthropic's IPO prospectus reveals the company's heavy reliance on select customers and major tech giants, such as Amazon and Alphabet's Google, for its growth. Seventy-one percent of its sales in 2025 were routed through cloud partners, with the two tech behemoths accounting for 47% of the company's annual revenue. These cloud providers also serve as significant investors in Anthropic and compete with it in the AI space.

Despite these connections, Anthropic maintains that its partnership with cloud platforms provides it a significant advantage in reaching customers and accelerating market penetration. However, the prospectus also acknowledges the complexity and potential conflicts of interest arising from these relationships, as the cloud providers gain visibility into Anthropic's pricing and commercial terms.

The company's cash flow is increasingly dependent on these third-party collections, which collected 60% of outstanding customer bills at the end of 2025. Anthropic's customer base is concentrated, with two unnamed clients contributing 12% of the company's revenue in 2025. The prospectus highlights the challenge of managing customer contracts, as many key clients lack long-term commitments.

Additionally, Anthropic's financial reporting for sales made through cloud marketplaces differs from that of its rival OpenAI, potentially contributing to discrepancies in reported revenue figures.