Eseandre Mordi
Public quarterly filings have unexpectedly revealed the extent of Amazon and Google's ownership stakes in Anthropic, the AI startup behind the Claude model family. Analysis of Q3 2025 reports from both companies shows they recorded substantial investment gains linked to Anthropic's surging valuation.
Amazon disclosed a $9.5 billion pre-tax gain, explicitly citing its Anthropic investment. Google reported $12.8 billion in non-operating income, largely from unrealized gains in non-marketable equity securities—analysts believe this stems from the same source. Working backward from these figures suggests Amazon owns roughly 7.8% of Anthropic while Google holds around 8.8%, giving them a combined stake exceeding 16% in one of the world's most valuable AI startups.
Deedy's Analysis: The Math Behind the Stakes
A recent analysis by trader Deedy breaks down the numbers. Anthropic's valuation jumped from $61.5 billion in March 2025 to $183 billion in September 2025—a $121.5 billion increase. Based on Amazon's $9.5 billion gain, this implies a 7.8% ownership stake. Google's reported $10.7 billion to $12.8 billion gain points to an 8.8% stake, now worth approximately $16.1 billion.
These calculations offer a rare quantitative glimpse into how much of Anthropic's equity rests with its strategic partners, even though neither company has publicly confirmed exact percentages.
Anthropic's Valuation Boom and Strategic Importance
Founded by former OpenAI researchers, Anthropic has rapidly emerged as a central player in the AI ecosystem. Its Claude language models stand among the leading alternatives to OpenAI's GPT series, and the company's valuation surge reflects strong investor confidence in its underlying technology. Anthropic's $183 billion valuation—up nearly 200% year-to-date—underscores both market enthusiasm and Big Tech's race for AI dominance.
Amazon has invested $8 billion total, using Anthropic models to power AWS Bedrock, its generative AI platform. Google, an early backer, continues integrating Anthropic's systems into Google Cloud offerings, aligning the partnership with its Gemini model strategy. This dual alignment positions Anthropic as a shared AI infrastructure partner for both tech giants—an unusual yet highly strategic arrangement.
Implications for the AI Industry
The financial data hints at deeper strategic coordination among AI powerhouses. While OpenAI remains closely tied to Microsoft, Anthropic's dual partnerships with Amazon and Google create a counterbalance in the global AI landscape. These stakes represent more than simple investments. They give both firms partial exposure to one of the few independent leaders in AI model training, provide competitive leverage in cloud computing, inference scaling, and model access, and blur traditional lines between competitors as Amazon and Google now share financial interests in the same AI startup.
If Anthropic continues its exponential rise, these holdings could become among the most lucrative—and strategically vital—tech investments of the decade.
Eseandre Mordi
