Anthropic is considering an unusual combination of IPO controls designed to reduce early trading volatility: allowing some existing shareholders to sell a limited number of shares on the first trading day while extending the lockup period beyond the typical 90-to-180-day range. The company confidentially filed its S-1 with the SEC on June 1, 2026, with a public filing expected by late August, and its IPO is projected for October 2026. Estimates suggest the offering could raise upwards of $60B and value Anthropic between $1 trillion and $2 trillion. The company completed a $65B Series H funding round in May 2026, lifting its private valuation to roughly $965B, while reported Q2 2026 revenue exceeded $11.5B, implying an annualized run rate of around $65B. Anthropic is also reportedly planning to require employees to use 10b5-1 trading plans, which schedule insider sales in advance. Its proposed governance structure would preserve founder control through super-voting shares and a dedicated trust, without offering public investors concessions over board control. The public S-1 should detail the lockup period, the share percentage eligible for day-one sales and the governance arrangements.