OpenAI Regains Secondary Market Investor Interest, Though Anthropic Remains Top Target
OpenAI is experiencing a resurgence in investor demand on the secondary market, driven by the release of its GPT-5.6 models and the success of its Codex AI coding agent. Although Anthropic remains the most sought-after target with a $1.2 trillion valuation, OpenAI's valuation has risen to $933 billion. This shift highlights how product updates and user growth can quickly restore investor confidence in private AI giants. It also reflects a broader trend where investors use OpenAI's relatively lower valuation to hedge their positions in Anthropic. Despite OpenAI's recovery, Anthropic still dominates secondary market demand with a five-to-two buyer ratio over OpenAI. Additionally, while OpenAI's GPT-5.6 Sol model is highly competitive, independent tests show it still trails behind Anthropic's Claude Mythos and Fable models.
## BACKGROUND
Since major AI startups like OpenAI and Anthropic are not publicly traded, investors must buy shares on the secondary market from employees or early backers. OpenAI Codex, released as a CLI and integrated agent in April 2025, helps automate complex software engineering tasks, contributing to OpenAI's enterprise user growth.