Anthropic said on June 1 that it confidentially submitted a draft registration statement to the U.S. Securities and Exchange Commission for a proposed initial public offering of common stock. The new report adds that Polymarket odds of Anthropic listing before OpenAI rose to 81%, up 56% over 24 hours. Anthropic has not set a timetable for the offering. The filing remains subject to SEC review and market conditions, and no share count or offering price has been disclosed.