Anthropic's IPO filing points to Amazon as the biggest winner, not venture backers

Amazon's convertible notes and preferred stock could give it far more than the VC firms, though a 12% conversion cap limits its share count.

Anthropic's public filing shows that venture backers such as Menlo Ventures and Sequoia are set to earn billions from its IPO, yet none of them holds the 5% needed to appear among principal stockholders, because at a $965 billion private valuation even a 1.5% stake is huge. The larger beneficiary looks to be Amazon, which holds convertible notes with $6.2 billion in principal, valued at $97.9 billion by Amazon as of June 30, plus $10 billion of nonvoting preferred stock bought in the latest two funding rounds, bringing its total investment to about $18 billion. Those notes can convert into as many as 1.84 billion shares, but a 12% cap applies unless Amazon waives it. Anthropic also reported a non-cash $72.4 billion charge for the first half of 2026 tied to the rising value of those notes and related liabilities. Google, which held about 14% in early 2025 and has since been diluted to an estimated 5.6%, is also set for gains, while Anthropic has committed at least $110 billion to AWS over ten years and at least $114 billion in cloud commitments to Google through 2033.