Two US firms filed a lawsuit in 2005 against major Chinese vitamin C exporters alleging that the exporters formed a price-fixing cartel, which was coordinated by the China Chamber of Commerce for Import and Export of Medicines and Health Production, to control prices of the market since 2001. They claimed that vitamin C customers in the US paid more for vitamin C as a result of the alleged cartel. But the Chinese manufacturers argued that their average export price of vitamin C to the United States was $4.57 per kg while the global average was $4.63. In 2005, China made 60% of the world's vitamin C supply, with the four leading Chinese producers making 60,000 tons, and about 80% of that was exported.

One of the Chinese companies being sued is Hebei Wellcome Pharmaceutical Co. Ltd., a majority-controlled subsidiary of North China Pharmaceutical Co. Ltd. (NCPC).

The litigation is ongoing, but the plaintiffs recently added North China Pharmaceutical Co. Ltd. to the lawsuit. NCPC declined to comment on this development but said it had hired Baker & McKenzie LLP to defend itself.

According to Huang Yong, Director of Competition Law Center of China Foreign Trade University, the plaintiffs added NCPC to the lawsuit due to following two motivations: 1) As parent company of Hebei Wellcome, NCPC may be aware of Hebei Wellcome’s price-fixing practices, and adding it to the lawsuit will allow the plaintiffs more access to evidences; and 2) NCPC is much more resourceful financially, thus will be in a better position to pay for potentially large compensations that the courts may reward plaintiffs.