Anthropic: AI company accuses Alibaba of large-scale attempt to copy Claude model

US firm alleges operators linked to Alibaba’s Qwen AI lab used thousands of accounts to access Claude in what it calls its largest known distillation attack

Anthropic has accused Alibaba of carrying out a large-scale campaign to copy the capabilities of its Claude artificial intelligence model, according to a report by The Wall Street Journal.

In a June 10 letter to US senators Tim Scott and Elizabeth Warren, Anthropic alleged that operators linked to Alibaba and its Qwen AI lab conducted what the company described as the largest known distillation attack against Claude.

According to the report, the campaign involved nearly 25,000 fraudulent accounts and approximately 28.8 million interactions with Claude between April 22 and June 5.

Anthropic said the activity targeted some of Claude’s most advanced features. These included software engineering, agentic reasoning and long-horizon task planning.

The company argued that such campaigns allow rival AI developers to replicate advanced model capabilities without investing in the significant research, development and computing resources required to build frontier AI systems.

Anthropic also called on US lawmakers and government agencies to strengthen protections against unauthorized model-copying efforts. The company urged officials to impose stricter controls on access to advanced US computing infrastructure and introduce penalties for organisations involved in such activities.

In artificial intelligence, model distillation refers to training a smaller or less capable AI system using outputs generated by a more advanced model. Developers commonly use the technique for legitimate purposes. However, leading AI companies argue that unauthorized use of frontier models may violate terms of service and raise intellectual property and national security concerns.

The allegations come as competition between the United States and China intensifies in the AI sector. Washington has tightened export controls on advanced chips and AI technologies, while Chinese technology companies continue expanding their large language model offerings.

Alibaba has not publicly responded to Anthropic’s allegations.