Anthropic cuts top-tier AI access after US foreigner ban
US-based AI firm Anthropic has blocked access to its newest models, Claude Fable 5 and Claude Mythos 5, for all foreign nationals following a government order citing national security. The move escalates tensions with the Trump administration and raises concerns over the company's IPO plans.
Anthropic, headquartered in San Francisco, said Friday it has cut access to two powerful artificial intelligence (AI) models after a United States government order citing national security concerns. The sudden block marks a major escalation in Anthropic’s growing showdown with the Trump administration after failed negotiations earlier this year over potential US military and intelligence use of its technology.
The company said it received a directive to block its Claude Fable 5 and Claude Mythos 5 for all foreign nationals. Fable 5 is publicly available, while Mythos 5 is mostly restricted to vetted organizations. The ban applies to foreigners "whether inside or outside the United States, including foreign national Anthropic employees." However, Anthropic said it had blocked access for all customers for now to ensure compliance.
Anthropic said its understanding is that the US government believes it has found a method to bypass, or "jailbreak" Fable, but the company's own tests found only minor vulnerabilities. The company said it was complying but disagreed that the findings should necessitate recalling a commercial model used by hundreds of millions.
This is the second major action by the Trump administration against Anthropic in months. Earlier, the Pentagon added Anthropic to a supply chain blacklist after the company refused to allow military use of its AI for domestic surveillance and fully autonomous weapons. The ban could potentially hurt Anthropic's plans for a public listing or IPO as early as fall 2026 at a valuation approaching $1 trillion.
