Last week, after Anthropic released Fable 5, the US government stepped in with a stop order. It seems that under EAR (Export Administration Requirements), the technology is too much for foreign persons to have access to. This set of rules covers national security and foreign policy interests, and basically means we don’t want others to have power that could be used against us. This is part of a recurring issue that has hit PKzip, PGP, and other software packages in the past, and it means that we sometimes have to wait until things sort themselves out. There’s a lot of conspiracy stuff surrounding this, but I’m not buying into all of the stories until we have more details.

Anthropic has suspended all access to its new AI models Fable 5 and Mythos 5 to comply with a government order citing national security concerns.
Source: Anthropic Blocks All Customers’ Access To Fable 5 And Mythos 5