Anthropic’s active preparation for a November 2026 IPO, including formal marketing targeted for the week of November 9 and a potential listing before Thanksgiving, drives the 96.5% market-implied probability it will reach public markets ahead of OpenAI. The company has advanced its S-1 filing, secured substantial private funding at near-trillion-dollar valuations, and positioned itself for a debut potentially exceeding $2 trillion amid strong revenue growth in its Claude large language models. OpenAI, by contrast, has explicitly deferred any 2026 listing, with CEO Sam Altman citing the need to address AI safety and alignment requirements before facing public-market pressures, while pursuing a $30 billion private round at roughly $1.4 trillion. Traders assign high confidence to Anthropic’s timeline because its process is further along and nearer term, though realistic risks such as SEC delays, shifting market conditions, or unexpected regulatory scrutiny on frontier AI deployments could still alter the outcome.