Anthropic is considering a plan that would let existing shareholders sell part of their holdings in its initial public offering, according to people familiar with the matter. The company is also weighing a longer-than-usual post-listing lock-up period for share sales, the report said. The number of shares that current holders may be allowed to sell, and which shareholder groups could participate, remain unclear. Anthropic is reportedly planning to publicly file its IPO prospectus after Labor Day in the US, with the offering likely in late September or early October, though the timetable could still be delayed.