The US government has allowed Anthropic to restore access to Claude Mythos 5 for a limited group of “trusted” American organizations that operate or defend critical infrastructure. The move partially reverses a June 12 export-control order that forced Anthropic to disable Mythos 5 and Fable 5 for all users over national security concerns.
More than 100 companies and institutions, including many Fortune 500 firms, are expected to get access.
Anthropic calls Mythos 5 its strongest cybersecurity model. The company says it is built on the same underlying model as Fable 5, but with some safeguards lifted for vetted cyber-defense use through its Project Glasswing program.
The Trump administration has not publicly detailed how approved organizations are being selected. Commerce Secretary Howard Lutnick said in a letter cited by Reuters that Anthropic had made “significant progress” in addressing risks linked to the models, but safeguards remain unclear. Restrictions continue for organizations not on the approved list.
Fable 5, Anthropic’s more public-facing model, remains restricted for now.
Why was this model banned before?
The model was not permanently banned, but access was suspended after a US export-control order on June 12. The order required Anthropic to block foreign nationals from using Mythos 5 and Fable 5. Anthropic said it disabled both models for all users to comply.
The US government cited national security concerns.Officials were worried that powerful AI models could be misused by military intelligence users in China, Russia or other countries of concern. Anthropic said it understood the government’s concern involved a possible “jailbreak” that could bypass a safeguard meant to stop Fable 5 from being used to identify software vulnerabilities.
