Chinese shares opened lower on Friday as tech stocks took a hit after U.S. artificial intelligence company Anthropic accused Chinese e-commerce giant Alibaba Group (HKG:9988) of extracting the capabilities of its Claude AI model.

The Shanghai Composite Index, the main gauge of Chinese stocks, opened 0.5% lower at 4,098.69. The Shenzhen Component Index declined 0.8% to 16,211.41.

Anthropic alleged that between April 22 and June 5, Alibaba conducted a distillation effort, in which a less capable model is trained via the outputs of a stronger one, using nearly 25,000 fraudulent accounts to generate nearly 29 million exchanges with Claude.

The move furthered China's ability to reach the advanced capabilities of Claude's AI model, Mythos ⁠Preview, Anthropic claimed.

However, Nomura analyst Jialong Shi told The Wall Street Journal: "Given this is not the first distillation allegation targeting Chinese firms, I expect the reputational damage ... to be small."