WASHINGTON, June 12 — The US government has issued an export control directive to suspend all access to Fable 5 and Mythos 5, citing national security authorities.
This move has led Anthropic to abruptly disable Fable 5 and Mythos 5 for all its customers to ensure compliance. The directive was received by Anthropic today at 5:21pm (ET) and did not provide specific details of the national security concern. The government’s decision is based on its belief that it has become aware of a method of bypassing, or “jailbreaking” Fable 5.
According to Anthropic, this technique involves asking the model to read a specific codebase and fix any software flaws. The company has reviewed a demonstration of this technique and found that it can identify a small number of previously known, minor vulnerabilities.
These vulnerabilities appear relatively simple, and Anthropic has found that other publicly-available models are able to discover them as well without requiring a bypass.
In fact, the company has validated that the level of capability displayed in the report that is believed to be the basis of the government’s directive is widely available from other models, including OpenAI’s GPT-5.5. The government has only given Anthropic verbal evidence of a potential narrow, non-universal jailbreak.
The company has reviewed a report that it believes is the basis of the government’s directive and has found that the technique is used by defenders who keep systems safe. The suspension of Fable 5 and Mythos 5 will not affect access to other Anthropic models. Anthropic has stated that it will share more details about the directive and its implications over the next 24 hours.
Anthropic’s decision to comply with the directive highlights the complex relationship between technology companies and governments.
The company’s ability to disable Fable 5 and Mythos 5 for all customers demonstrates its commitment to ensuring compliance with US regulations. However, the lack of specific details about the national security concern raises questions about the implications of this directive.
Looking ahead, it will be crucial to monitor how this situation unfolds and what steps Anthropic and the US government take next.
The directive may have a significant impact on the development and deployment of advanced technologies like Fable 5 and Mythos 5. As the story continues to develop, the intersection of technology and national security will remain a critical area of focus.
