Anthropic’s planned November IPO, targeting a valuation above $2 trillion, stands as the dominant catalyst behind the 92% market-implied odds favoring it over OpenAI by year-end. The company’s latest $965 billion private mark from its May Series H already exceeds OpenAI’s $852 billion March valuation, supported by accelerating revenue—Q3 run-rate revenue reached $16.8 billion with adjusted profitability—and strong enterprise adoption of Claude models. OpenAI, by contrast, has deferred its public listing until 2027 at the earliest while pursuing a $1.4 trillion pre-money funding round. Traders price in the likelihood that Anthropic’s public debut will establish a durable lead before December 31, though a sizable OpenAI private round closing near or above $1.4 trillion or an IPO valuation shortfall could narrow the gap.