Tianjin High People's Court put a closure to the six-year patent dispute between French firms Bayer Agricultural Science, Bayer Corp Science (China) and Anhui firm Huaxing Chemical, upholding the trial court decision, which denied Bayer's allegation.
In June 1988, another French firm Rhdne-poulenc S.A. filed a patent application of a pesticide by the name of Fipronil with SIPO and would obtain a patent in October 1994. Rhdne-poulenc also filed for administrative protection of chemicals of pesticide with the then-Ministry of Chemical Industry in February 1994 and would acquire the approval within the same year. The patent and administrative protection would then be assigned to Bayer Agricultural Science later in the year.
In September 2003, Bayer Agricultural Science and Bayer Corp Science discovered Fipronil in a Tianjin warehouse. Huaxing sold the goods to Shenzhen Food & Oil. Bayer then downloaded Huaxing's advertisement on Fipronil and had the content notarized before filing a case to Tianjin No.1 Intermediate People's Court.
In July 2008, Tianjin No.1 Intermediate Court found that there was insuffcient evidence to support any Bayer's claims. The two Bayer companies then appealed to the High Court and sought 20 million yuan in damages.