A rare public clash has broken out between Alibaba and Chinese authorities over the authenticity of the merchandise sold on the Chinese e-commerce giant's sites, especially its popular consumer to consumer site Taobao.

In an unusually strongly worded white paper, the State Administration of Industry and Commerce said many of the products sold on Alibaba's websites were substandard, violated trademarks or were illegal. The release of the documents comes less than a week after the agency unveiled a survey that found only 37.25 percent of the goods the authorities examined on Taobao to be genuine.