Anthropic on September 1, 2026, announced Enterprise Frontier Safeguards (EFS), an offering that combines the privacy of zero data retention with automated safeguards for detecting misuse by storing activity data in cloud infrastructure controlled by the customer rather than by Anthropic. The system will roll out to customers in phases beginning later in the fall of 2026. According to Anthropic, Mythos-class models such as Claude Fable 5.1 represent a major increase in intelligence and agentic…