Anthropic Suspends Its Most Advanced AI Models After U.S. Government Order

Anthropic said on Friday that it has disabled access to its two most advanced models, Claude Fable 5 and Claude Mythos 5, after receiving a national security directive from the U.S. government. The move came just days after Fable 5 was released to the public.

According to the company, the U.S. Commerce Department ordered it to restrict use of the models by any foreign national, whether inside or outside the United States, including Anthropic employees with foreign citizenship. Anthropic said the government did not fully explain the security concerns behind the order.

The company said its understanding is that the concern involves attempts to bypass some of the models’ safeguards, which could be used to find software vulnerabilities and carry out advanced cyber operations. Rather than block only foreign users, Anthropic chose to suspend both models for all users temporarily to ensure full compliance.

Anthropic criticized the decision, saying governments should be able to stop unsafe deployments only through a transparent, fair, clear process based on technical facts, and that this action did not meet those standards. The company has also recently been placed on the Pentagon’s blacklist as too dangerous for government use, a designation it has sued the Trump administration over. The episode could signal a shift in U.S. policy, moving export restrictions from chips and hardware to AI models themselves.