Anthropic is restoring global access to its Claude Fable 5 and Mythos 5 models after the US government lifted export controls that had suspended availability for all users. Fable 5 will be available globally starting July 1 on the Claude Platform, with usage limits applying through July 7 before switching to credit-based access.
- Access restrictions were imposed on June 12 due to an Amazon report identifying a method to bypass Fable 5's safeguards, prompting immediate suspension for all users.
- Testing confirmed that the reported vulnerability identification and exploitation demonstration capabilities were not unique to Fable 5 but were present in other models like GPT-5.5 and Kimi K2.7.
- Anthropic trained an improved safety classifier that blocks the specific bypass technique in over 99% of cases, redirecting blocked requests to Opus 4.8.
- Mythos 5 access has been restored for a set of US organizations following government approval on June 26, while broader expansion continues through the Glasswing program.
The company is collaborating with Amazon, Microsoft, Google, and other partners to develop a shared industry framework for assessing AI model jailbreaks and severity. This initiative aims to establish consistent standards for triaging safety findings and communicating risk levels to government and industry stakeholders.