Anthropic details distillation campaigns from Alibaba, Moonshot AI, and DeepSeek

A new report released Thursday by Anthropic alleged persistent distillation attacks by China-based AI companies, which have escalated in recent months as competition in the space has intensified.

“Over the last several months, unauthorized labs have developed increasingly sophisticated methods to circumvent our defenses and harvest the capabilities of US frontier models,” the report reads. “The campaigns we identified targeted some of Claude’s most valuable capabilities, including agentic capabilities and tool use, coding and data analysis, and logical reasoning.”

Anthropic previously spoke out about distillation attacks in February, even calling out specific labs. OpenAI has reported similar activity, which it attributed to DeepSeek specifically. But the campaigns detailed in Anthropic’s new report are both larger and more aggressive. All told, the company observed nearly 200 million exchanges linked to distillation attacks, attributed to five separate campaigns.

Broadly, distillation attacks focus on extracting the chain of thought from a model’s response to various queries. That chain of thought can then be used to train a smaller model on general reasoning ability through supervised fine-tuning.