Anthropic, the AI safety company behind Claude, filed confidential IPO paperwork with the SEC on 1 June 2026. UK investors cannot buy Anthropic shares on the open market yet. The company has not announced a public listing date, ticker symbol, or share price. Anthropic has explicitly warned that any unapproved sale or transfer of its private shares is void. Accredited investors may access shares through secondary-market platforms such as Forge Global, EquityZen, or Hiive, subject to transfer restrictions and significant risk. Anthropic is targeting a public listing as early as October 2026, with a broader window of late 2026. Once listed on the Nasdaq or NYSE, shares will be available to UK retail investors through any standard brokerage with US market access. While Anthropic remains private, three publicly traded companies offer indirect exposure: Amazon (AMZN), Alphabet / Google (GOOGL), and Salesforce (CRM). Reuters reported that Salesforce's stake in Anthropic was worth approximately $5 billion in June 2026.