Anthropic said on Friday it will "abruptly disable" its most advanced artificial intelligence (AI) models, Claude Fable 5 and Mythos 5, for all users after the U.S. government ordered it to suspend access to the models for foreign nationals, whether inside or outside the U.S., citing national security concerns.
The AI company said it received an order at 5:21 p.m. ET, instructing it to suspend all access to the models by foreign nationals. It said that it believed there was a "misunderstanding" and that it is working to restore access to the models as soon as possible. Access to other models will not be affected by the export control directive.
"Our understanding is that the government believes it has become aware of a method of bypassing, or 'jailbreaking' Fable 5," the company said.
"We reviewed a demonstration of this specific technique being used to identify a small number of previously known, minor vulnerabilities. These vulnerabilities all appear relatively simple, and we have found that other publicly-available models are able to discover them as well without requiring a bypass."
The unexpected move comes days after the launch of Claude Fable 5 and its counterpart Mythos 5, which uses the same underlying model but with the safeguards lifted in some areas, like cybersecurity. The latter, described as having the "strongest cybersecurity capabilities of any model in the world," remains accessible to a vetted group of cyber defenders and critical infrastructure operators.
