UK eases Mythos 5 AI restrictions for select organisations

The UK government has lifted some restrictions on Mythos 5, allowing select organisations to access the advanced AI model once more. Anthropic’s strong focus on safety has played a key role in this decision, making it the first to benefit from the change. On 26 June, Commerce Secretary Howard Lutnick wrote to Anthropic, acknowledging major progress in their collaboration. The government has now introduced a tiered access system called the Permission Layer, replacing blanket restrictions with selective approvals.

Organisations listed in Annex A of the letter, including their foreign national employees, no longer need a licence to use Mythos 5. The model is now available to a government-approved group, while others remain blocked. Fable 5, the consumer-facing version, stays restricted for now.

Anthropic is working to restore Mythos 5 access for approved providers as quickly as possible. At the same time, it continues to cooperate with officials to expand availability and eventually reinstate Fable 5 for general use. The distinction between Mythos 5 and Fable 5 highlights the priority given to enterprise and API access for frontier AI. The new approach gives approved organisations a competitive edge by granting them early access to advanced AI tools. Mythos 5 is now operational for select users, but Fable 5 remains off-limits to the public. The government’s shift to targeted permissions marks a significant change in how frontier AI is regulated.