Anthropic Halts Claude Fable Access Over US Export Ban

The U.S. government ordered Anthropic to immediately block foreign access to its Claude Fable and Mythos 5 models over alleged jailbreaks and vulnerabilities that purportedly allow bypassing model safeguards; Anthropic suspended global access to comply, disputes the sufficiency of the evidence, and is negotiating with officials while partners sever connections. The report emphasizes uncertainty about the link between public jailbreak demonstrations and the government-provided demonstrations, describes potential easy-to-exploit weaknesses, and highlights the operational and user-impact consequences of the directive.