Anthropic Restricts Mythos Due to Regulatory Pressure; Mythos 2 Trained but Unreleased

Anthropic's decision to hold back a trained frontier model because of regulatory pressure marks a shift in how labs weigh release against compliance risk. The affected parties are not just Anthropic but the broader frontier ecosystem, where completed-but-unreleased models may become a recurring outcome rather than an exception. The open question is whether this restraint reflects a temporary posture toward pending rules or a durable change in how labs sequence training and deployment.