Anthropic’s Fable 5 and Mythos 5 AI models are now back online after nearly three weeks of suspension under US export controls. The company has now confirmed that it has restored the access for Fable 5 globally and is also following new safeguards developed in association with the US government. “Claude Fable 5 and Mythos 5 redeployed. Access to Claude Fable 5 and Mythos 5 is now restored,” said the company. On June 12, the US government imposed export restrictions on Anthropic’s newest models, Claude Fable 5 and Mythos 5, citing national security concerns. The directive forced Anthropic to suspend access to all users, as the company had no reliable way to verify nationality in real time. As of June 30, the controls were lifted. Fable 5 is now available worldwide via Claude.ai, Claude Code, and Claude Cowork, while Mythos 5 has been restored for select US organizations under government approval. Safeguards strengthenedAnthropic said the suspension was triggered by a report showing that Fable 5 could be prompted to identify software vulnerabilities and demonstrate exploit code. In response, the company worked with government partners to train an improved safety classifier that blocks such behavior in over 99% of cases. Requests flagged by the classifier will be redirected to Claude Opus 4.8, ensuring users can continue routine coding tasks without disruption. The company acknowledged that the stricter safeguards may occasionally block benign requests but emphasized that this “safety margin” is necessary to prevent misuse.Export controls on Fable 5 and Mythos 5 have been lifted“Claude Fable 5 will be available again globally tomorrow.After a series of productive conversations with the US government, we're redeploying the model with a new set of classifiers to target and block more cybersecurity tasks. In the near term, some routine tasks like coding and debugging will fall back to Opus 4.8. We’ll continue to refine these classifiers over the coming weeks to reduce false positives and better distinguish genuine misuse from legitimate requests.We’ve also begun drafting a consensus framework—with Amazon, Microsoft, Google, and other Glasswing partners—for assessing the severity of AI jailbreaks and how AI developers should respond to them. We invite other industry partners and model providers to join us in this effort.Finally, we’re scaling up our collaboration with the US government on model testing and safeguards. This will include pre-release access to models and safeguards for evaluation, information sharing on jailbreaks and misuse, and dedicated resources for joint research.Thank you to our users for your patience, and to our partners across the government, industry, and the research community who worked alongside us to make Fable 5 available again,” said Anthropic in a post on X.Deeper government collaborationThe company pledged to expand cooperation with US agencies, including:* Pre-release government access to frontier models for independent evaluation.* Rapid information sharing on safeguards and misuse patterns.* Joint research teams dedicated to AI security and red-teaming.* Contributions toward a voluntary industry standard for frontier model safety.Anthropic said these commitments align with the June 2 AI executive order signed by President Trump, which calls for stronger oversight of advanced AI systems.