Anthropic is restoring full access to Claude Fable 5 starting tomorrow, weeks after a US government directive forced the company to suspend the model for all users. The government order arrived on June 12 and required Anthropic to block foreign nationals from using Fable 5 and its more capable Mythos 5 model. Since the rule took effect immediately and Anthropic had no way to verify a user’s nationality in real time, the company suspended both models entirely rather than risk a violation.
What triggered the shutdown
The restrictions followed a report from Amazon researchers, who found a way to prompt Fable 5 into identifying software vulnerabilities its safeguards were designed to block. In one instance, the model generated code showing how a flaw could be exploited.
Anthropic says it later confirmed that several less capable models, including Opus 4.8 and competing models, could produce similar results, which suggests the bypass didn’t hinge on capabilities unique to Fable 5.
Return terms and new safeguards
Fable 5 will be available globally starting July 1 to users on the Claude Platform, Claude.ai, Claude Code, and Claude Cowork. Pro, Max, Team, and select Enterprise plans will get the model included for up to half their weekly usage limits through July 7, after which usage will draw from credits. Access on AWS, Google Cloud, and Microsoft Foundry will follow.
Mythos 5 already returned earlier for a limited set of approved US organizations, and Anthropic says it has received further government clearance to expand that access on June 26. The company has revealed that it built a new safety classifier that blocks the flagged technique in more than 99 percent of cases and is working with Amazon, Microsoft, and Google on a shared industry standard for grading the severity of AI jailbreaks going forward.