Anthropic Says New Defenses Cut Distillers' Claude Reasoning Extraction 10 to 100 Times
Anthropic says its new anti-distillation defenses cut the reasoning tokens attackers extract from Claude by 10 to 100 times. The company's two-stage classifier, run on Claude Sonnet 5.5 and Opus 5.5, has a false positive rate under 0.1 percent. Anthropic also charges for requests blocked before Claude responds.