OpenAI has confidentially filed for a US initial public offering, joining rival Anthropic in seeking a stock market listing. No timeline or valuation has been officially confirmed, though reports suggest OpenAI is targeting up to $1 trillion. Anthropic filed on June 1 following a $65 billion funding round valuing it near $965 billion. Both filings mark a significant moment for the AI industry, with observers noting that these listings, alongside SpaceX's planned IPO, represent the most consequential test of investor appetite for high-growth technology in a decade. OpenAI reports $2 billion in monthly revenue, over 900 million weekly ChatGPT users, and does not expect profitability until 2030.