On June 9, Anthropic released Claude Fable 5, the most capable model it has ever made, generally available. It also did something unusual: it shipped one model as two products, split not by capability but by a layer of safety classifiers. Fable 5 goes to the public. Its twin, Claude Mythos 5, the same underlying model with the cyber safeguards lifted, stays locked to a vetted group of cyber defenders and critical infrastructure operators. Anthropic calls Mythos 5 the strongest cybersecurity model in the world. The practical difference is this: Fable 5 routes flagged cyber, biology, chemistry, and distillation requests to the weaker Claude Opus 4.8, while Mythos 5 keeps the cyber capabilities available for vetted users. Both models cost $10 per million input tokens and $50 per million…