Microsoft's market capitalization near $3.93 trillion substantially exceeds the combined private valuations of Anthropic and OpenAI, recently marked between roughly $1.8 trillion and $2.5 trillion across secondary trading and funding rounds. Anthropic's May 2026 Series H priced it at $965 billion, with Q3 revenue reaching $16.8 billion, yet investor discussions have tempered November IPO expectations toward $1.5 trillion amid slower sequential growth. OpenAI's March round valued it at $852 billion, with secondary marks near $1.2 trillion and talks of a pre-IPO round at $1.4 trillion pre-money as its revenue run rate approaches $50 billion. These dynamics, alongside Anthropic's nearer-term IPO timeline versus OpenAI's 2027 plans, underpin the 75.5% market-implied odds favoring Microsoft through year-end.