US clears limited access to Anthropic’s Mythos 5 AI model

The US government has allowed Anthropic to restore limited access to its Mythos 5 AI model for selected trusted partners after addressing national security concerns, while restrictions on the Fable 5 model remain in place pending further review

New Delhi: US-based AI company Anthropic has won US approval to restore limited access to its powerful Mythos 5 artificial intelligence (AI) model to “certain trusted partners” after resolving the government’s national security concerns.

Commerce Secretary Howard Lutnick wrote to Anthropic’s chief compute officer that the company’s efforts with the US government to address risks associated with the models “have yielded significant progress”, multiple reports said.

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The clearance follows a government order issued two weeks earlier that abruptly barred Anthropic from giving foreign nationals access to Mythos 5 and a related model, Fable 5, over fears that security guardrails could be circumvented.

The company responded by disabling global access and undertook intensive talks to reach a resolution.

“In just two weeks, we have worked diligently to ensure America remains the global leader in AI while safeguarding our security,” Benno Kass, Commerce Department spokesman, was quoted as saying.

However, the recent letter does not mention any change to the government’s restrictions on the use of the Fable 5 model.

“We received notice from the US government that Mythos 5, our strongest cybersecurity model, can be redeployed to a small group of cyber defenders and infrastructure providers,” Anthropic said in a statement.

The company said it is working to provide access to the approved set of providers and restore their access to Mythos 5 as quickly as possible.

The company expressed optimism about the progress and said it will work with the government to expand access to Mythos 5 and make Fable 5 available for general use again.

Fable 5 is prevented from responding to some queries, such as cybersecurity- and biology-related questions.

In those cases, Anthropic has said its Claude chatbot will route responses through a different model, called Opus 4.8.

Anthropic had objected to the government’s decision to impose export controls in a blog post, saying such standards, if applied across the industry, “would essentially halt all new model deployments for all frontier model providers.”