The United States has placed Fable 5 and Mythos 5 under export controls for foreign access.

The letter sent to Anthropic

Axios reports that US Commerce Secretary Howard Lutnick sent a letter to Anthropic on 12 June 2026 . According to Axios, the letter provides that the Mythos 5 and Fable 5 models are to be made subject to export controls for any destination outside the United States and in respect of foreign persons present in US territory .

CNBC reports that Anthropic received a directive from the US government citing national security authorities . The outlet states that this directive required the suspension of access to the Fable 5 and Mythos 5 models for any foreign national . CNBC also reports that Anthropic disabled access to those two models for all of its customers, while the company’s other models are unaffected .

CyberScoop attributes the directive to a letter sent by Howard Lutnick to Anthropic chief executive Dario Amodei . The site states that the text places Fable 5 and Mythos 5 under export controls and prohibits their use by foreign nationals, both in the United States and outside US territory .

The geographical and personal scope of the controls

Axios reports that, on 12 June 2026, US Commerce Secretary Howard Lutnick sent a letter to Anthropic concerning the Mythos 5 and Fable 5 models . The geographical scope mentioned by Axios covers any destination outside the United States, with export controls applied to those models . Axios also mentions foreign persons present in US territory among the access arrangements covered by the letter .

CyberScoop reports that the letter sent to Dario Amodei places Fable 5 and Mythos 5 under export controls prohibiting their use by foreign persons, whether they are in the United States or outside the United States . The same article states that the scope includes Anthropic’s foreign employees and that Anthropic announced the disabling of the two models because of the breadth of the restrictions .

Forbes reports, citing Axios, that a licence would be required for the export, re-export or in-country transfer of the Mythos 5 and Fable 5 models . According to CyberScoop, the Department of Commerce letter does not set out the national security concern invoked for the measure .

The access suspension announced by Anthropic

CNBC reports that Anthropic disabled access to Fable 5 and Mythos 5 for all customers following a US export control directive citing "national security authorities" . According to CNBC, the company presented this disabling as a measure intended to ensure compliance with the directive, after receiving an order requiring it to suspend all access to the two models "by any foreign national" .

CyberScoop reports that the letter from Commerce Secretary Howard Lutnick to Dario Amodei placed Fable 5 and Mythos 5 under export controls and prohibited their use by foreign nationals, in the United States or outside the United States . The outlet states that access to Anthropic’s other models was not affected .

The specialised source LDS cites Anthropic’s statement that "Access to all other Anthropic models will not be affected" . It also reports that Anthropic described the effect of the directive as an abrupt disabling of Fable 5 and Mythos 5 for all customers .

The stated rationale and the documentary limits

CNBC states that Anthropic disabled access to Fable 5 and Mythos 5 in order to comply with a US export control directive citing national security authorities . The same outlet reports that the order received by the company required the suspension of all access to the models by foreign nationals .

CyberScoop reports that the letter sent to Anthropic by Commerce Secretary Howard Lutnick does not set out the specific national security rationale invoked . According to source 184, Anthropic stated that the government had not provided detailed written evidence and referred instead to verbal evidence of a potential, narrow and non-universal circumvention of Fable 5 .

CyberScoop reports that Anthropic disputed the seriousness of the finding . According to that outlet, the company stated that it had reviewed a report which it believes prompted the directive and concluded that the capabilities described were already available in other publicly accessible models, including OpenAI’s GPT-5.5 .

The sources available in this dossier do not reproduce the full text of the Department of Commerce letter and do not cite any decision published in the Federal Register .