On June 12, 2026 (US time), Anthropic disabled access to its top-tier AI models, Claude Fable 5 and Claude Mythos 5, for all customers in response to a directive from the US government. The export control order, issued under national security authorities, requires the company to stop foreign nationals from using the models. Anthropic is complying while openly disputing the basis for the action[1].
A directive to cut off access for foreign nationals
According to Anthropic, the directive arrived at 5:21 pm US Eastern time on June 12. Citing national security authorities, it requires the company to suspend access to Fable 5 and Mythos 5 for any foreign national, whether inside or outside the United States. The order even covers Anthropic's own foreign national employees[1].
Because carving out only foreign nationals is technically difficult, the company concluded that the only way to ensure compliance was to disable both models immediately for all customers. Access to Anthropic's other models is unaffected[1]. The directive was reported to have come from the US Department of Commerce[2].
Fable 5 had only recently become available, opening up the "Mythos-class" tier that sits above Opus to general users in early June 2026. The move effectively pulls a flagship model from the market shortly after its debut[1].
The concern centers on a "jailbreak"
Anthropic says the written directive did not spell out the specific national security concern. The company's understanding is that the government believes it has learned of a method for bypassing, or "jailbreaking," Fable 5's safeguards[1].
Anthropic states that it reviewed a demonstration of the technique and found that it surfaced only a handful of previously known, minor vulnerabilities, all of them relatively simple. The company adds that such flaws can be discovered without any bypass by other publicly available models as well, pointing to OpenAI's GPT-5.5 as an example[1].
Fable 5 includes a classifier that, when it detects high-risk requests in areas such as cybersecurity or biology and chemistry, routes the response to the next-tier model, Claude Opus 4.8, instead of Fable 5 itself. Anthropic says that before launch it ran a combined total of thousands of hours of red-teaming with the US government, the UK AI Safety Institute (UK AISI), and several third-party organizations, and that no one has yet found a "universal jailbreak" capable of broadly disabling the model's safeguards[1].
Anthropic argues a recall over a narrow flaw is excessive
While removing access in line with the directive, Anthropic made clear it disagrees with the decision. The company explains that no provider can currently build a model with perfect jailbreak resistance, and that it said from the outset that a universal jailbreak would likely be found eventually. It has therefore adopted a defense-in-depth strategy designed to keep jailbreaks narrow or expensive to produce, paired with monitoring to detect and shut down attacks quickly[1].
On that basis, the company states that "we do not believe a narrow potential jailbreak should be cause for recalling a commercial model deployed to hundreds of millions of people." If such a standard were applied across the industry, Anthropic argues, it could effectively halt new model deployments for every frontier model provider[1].
At the same time, Anthropic says it supports the government having the ability to block unsafe deployments, but that this authority should be exercised as part of a legal process that is transparent, fair, clear, and grounded in technical facts. The current action, it says, does not adhere to those principles[1].
Impact and what comes next
With the suspension in place, customers who relied on Fable 5 and Mythos 5 cannot use them for the time being. Anthropic apologized for the disruption, saying it believes the matter is a misunderstanding and that it is working to restore access as quickly as possible, with more details to follow within 24 hours[1]. Multiple outlets, including Bloomberg and CNBC, also reported that the company disabled the models to comply with the government directive[2].
Summary
Faced with a US export control directive requiring it to block foreign nationals, Anthropic disabled Fable 5 and Mythos 5 for all customers. The government is said to have concerns about a "jailbreak," but Anthropic counters that what was found amounts to minor, already-known vulnerabilities that do not justify recalling a commercial model. The company is complying with the order while disputing both its rationale and process, and says it aims to restore access soon.
