Anthropic has disabled access to its most advanced artificial intelligence models, including Mythos, following an unprecedented order by the Trump administration to keep the technology out of the hands of all foreign nationals.
The U.S. government told Anthropic to suspend access to the Fable 5 and Mythos 5 models by any foreign national “whether inside or outside the United States,” citing national security concerns, the company said in a statement. A U.S. official confirmed the Commerce Department sent the letter. The model developer has since shut off access to both systems to all customers to ensure compliance.
Never before has the U.S. government taken such sweeping measures to rein in foreign access to frontier AI models developed by an American company. Both the Trump and Biden administrations have limited access abroad to other consequential technologies such as semiconductors and supercomputers, and some have debated the merits of blocking access to AI models. But restrictions on the software itself have raised constitutional and commercial concerns.