Anthropic’s upcoming IPO is poised to generate significant returns for its early venture capital investors, including heavyweights like Menlo Ventures, Sequoia, Sound Ventures, and Spark Capital. Despite their lucrative stakes, none of these VC firms own more than 5% of the company, a rare scenario for a tech IPO. This is largely due to Anthropic’s substantial private valuation of $965 billion, where even a small percentage stake translates to billions in value, with Menlo Ventures’ position alone estimated around $14 billion.

Amazon stands out as the dominant financial beneficiary of the IPO, far surpassing the gains of traditional investors. Since first investing in Anthropic in 2023 with a commitment of up to $4 billion, Amazon has infused much larger sums in subsequent rounds. Rather than purchasing stock directly upfront, it deployed most of its investment as convertible notes, which convert into equity upon IPO, currently held at $6.2 billion principal. These notes were valued at nearly $98 billion on Amazon’s books as of mid-2026, reflecting Anthropic’s rapid valuation growth.

The terms of Amazon’s investment include a cap limiting its ownership to 12% of Anthropic’s partially diluted shares, although Amazon may waive this cap. Beyond convertible notes, Amazon also acquired $10 billion worth of nonvoting preferred stock across recent funding rounds. In total, Amazon has invested approximately $18 billion in Anthropic. Additionally, Anthropic has committed to spend over $110 billion on Amazon Web Services infrastructure over the next decade, creating a highly lucrative ongoing commercial relationship for Amazon.

Google also reaps windfalls from Anthropic’s rise. Having once held around 14% before dilution from new funding, its stake is now closer to 8%. Google has invested at least $10 billion recently and secured cloud service commitments exceeding $114 billion through 2033. While both Amazon and Google benefit enormously from Anthropic’s IPO and service contracts, Anthropic’s S-1 highlights the potential tension as these cloud providers also develop competing AI models, indicating complex dynamics ahead for the AI startup and its strategic backers.