Anthropic alleged in October 2026 that Chinese AI lab Zhipu distilled cyber capabilities from leading US AI models while developing GLM-5.3

Strengthening our defenses against distillation attacks

Anthropic describes new defenses against illicit distillation of Claude, including preserved thinking, a two-stage classifier, and account bans, which cut extracted reasoning tokens 10-100x. It argues distillation threatens national security and urges all developers and platforms to act.