In March, Anthropic's Claude "quietly deployed software to spy on China-based customers," reports the Washington Post — apparently to unmask Chinese rivals "suspected of hijacking its technology to make their own AI tools smarter." Last week Anthropic removed the spyware "after a software developer revealed its existence and privacy advocates criticized Anthropic, saying it had surveilled its own users." Anthropic's tracking code was designed in part to catch Chinese firms "distilling" its AI models, a technique that involves pressing a large, expensive AI system to serve as a tutor to a smaller, cheaper one. Asking the larger system huge numbers of questions — hundreds of thousands or more — generates responses that can be used to upgrade the power of the smaller one on the cheap. Distillation isn't illegal, and it has been used for years in the AI industry. But distillation without permission is against AI companies' rules, and, used effectively, is giving Chinese AI companies a major leg up, American AI companies say... Anthropic and ChatGPT-maker OpenAI have both accused Chinese AI companies of using this technique to build copycat AI models of their own.

In a May blog post, Anthropic said that Chinese companies' use of distillation, along with evading U.S. export controls on high-end computer chips, has allowed them to "trail closely" behind U.S. models. But if these techniques can be blocked, it might be possible for the United States to "lock in a 12-24 month lead" on Chinese capabilities, the company said... This month, Anthropic said in a letter to U.S. senators that was obtained by The Post that it uncovered a campaign in which Chinese tech giant Alibaba's Qwen AI team used roughly 25,000 fraudulent accounts to generate more than 28.8 million exchanges with Claude to improve its own technology. In February, Anthropic made similar accusations against the Chinese firms Deepseek, Moonshot and MiniMax and said the campaigns were "growing in intensity and sophistication...." Anthropic and OpenAI have appealed to the U.S. government, arguing that distillation amounts to intellectual property theft that harms the U.S. in the geopolitical AI contest....

That Chinese AI labs are using U.S. models to improve their own technology appears beyond dispute. In a February 2025 study, researchers from China's Peking University and the state-funded Chinese Academy of Sciences developed methods to detect signs of distillation in leading large language models. They concluded that, with the exception of ByteDance's Doubao, most domestic models they tested showed substantial evidence of distillation, mostly drawing from U.S. models... In one set of intensive tests, a Qwen model misidentified itself as Claude nearly a third of the time, the Chinese researchers found.

U.S. firms have also used distillation to piggyback on AI systems made by others. In 2024, OpenAI released a tool to make it easier for customers to distill its own models and produce data sets for AI training. SpaceX founder Elon Musk said in court testimony in May that his AI company xAI used distillation to train its models and that the technique is common throughout the industry.
The article also notes that Anthropic "said it has banned nearly 700,000 accounts that were using Claude in China." But the article includes this quote from Kyle Chan, a fellow at the Washington-based Brookings Institution's China Center. "Anthropic's framing is that this is a geopolitical contest for basically the future of the world and freedom and democracy. It's that this is not just undercutting the U.S. commercially, but undercutting American strategic advantage in the most powerful technology we know today."