Anthropic Files Confidential S-1 with SEC for IPO

AI safety research company Anthropic announced on June 1, 2026 that it had confidentially filed a draft S-1 registration statement with the U.S. Securities and Exchange Commission (SEC) for the purpose of an initial public offering (IPO) of its stock. After the SEC completes its review, the company will gain the option to conduct an IPO depending on market conditions. Official announcement

What Happened

Anthropic, PBC submitted a draft registration statement on Form S-1, with an IPO in mind, to the SEC on a confidential basis. The filing is part of a process that allows it to become public after SEC review, giving the company the option to pursue an IPO once the review is complete. Official announcement

The number of shares and the price have not been determined, and the announcement explicitly states that it is made pursuant to Rule 135 of the Securities Act and does not constitute a solicitation to sell securities. The size, price, and timing of the IPO are all unannounced, and whether it proceeds depends on market conditions and other factors.

On the same day, Anthropic announced Claude Opus 4.8 for coding, agent tasks, and the like.

Background and Significance

Anthropic is an AI company founded by former OpenAI executives, with its flagship products being the Claude series (Opus, Sonnet, etc.). This IPO preparation comes amid a rapid expansion of the company's valuation.

Most recently, on May 28, 2026, the company raised $6.5 billion in a Series H round, bringing its post-money valuation to roughly $965 billion (close to $1 trillion). This exceeds OpenAI's most recent valuation ($852 billion, March 2026), and Reuters reported the company as the "world's most valuable AI company." Reuters