U.S. Government Orders Anthropic to Disable Claude Fable 5 and Mythos 5 Over National Security Concerns
The U.S. government issued an export control directive on June 12, 2026, requiring Anthropic to disable its Claude Fable 5 and Mythos 5 AI models for all users, citing national security concerns. Commerce Secretary Howard Lutnick issued the order after the government became aware of a method for bypassing the models' safety guardrails. Anthropic publicly disagreed with the decision, calling the identified vulnerability minor and comparable to flaws in other publicly available models.
The U.S. government issued an export control directive on June 12, 2026, requiring Anthropic to disable its Claude Fable 5 and Mythos 5 artificial intelligence models for all users, citing national security concerns.
Commerce Secretary Howard Lutnick issued the letter at 5:21 p.m. ET, specifying that a license would be required for the export, re-export, or domestic transfer of these models. The directive required the suspension of access for any foreign national, regardless of their location, including foreign nationals employed by Anthropic.
To ensure compliance with the broad restrictions, Anthropic abruptly disabled the models for all customers. Existing sessions using Fable 5 were terminated with an error, and the model was removed from the Claude platform.
Anthropic stated its understanding that the government had become aware of a method for bypassing the safety guardrails of Fable 5. The company reviewed a demonstration of the technique and contended that the identified vulnerabilities were minor, relatively simple, and comparable to flaws discoverable in other publicly available models, including OpenAI's GPT-5.5.
"We disagree with this decision," Anthropic said in a public statement. "The discovery of a narrow, non-universal potential jailbreak should not necessitate the recall of a commercial model. If this standard were applied consistently, it would effectively halt all new model deployments across the frontier AI industry."
Anthropic criticized the process for lacking the transparency and technical grounding it believes should accompany such significant regulatory actions.
The suspension followed a separate controversy earlier in the week, when Anthropic faced backlash from developers for implementing "invisible" safety guardrails intended to prevent the use of Claude for training competing AI models. The company had agreed to make those safeguards visible before the government order forced it to pull the models entirely.
All other Anthropic models remained operational and unaffected by the directive. The company said it was working to restore access to Fable 5 and Mythos 5.
