According to reports in Japanese media, Nippon Steel has filed a lawsuit against Mitsui & Co for infringing on patents that cover nonoriented electrical steel sheet. The suit was filed on December 10 in the Tokyo District Court. Nippon Steel says Mitsui has been involved in deals between Toyota and Baoshan. In October, Nippon Steel had filed a lawsuit against Toyota and Baoshan Iron & Steel, a subsidiary of China's state-run China Baowu Steel Group for the same reason. Nippon Steel said that Baoshan supplies Toyota with products that violate Nippon Steel's patents, such as those covering the composition of steel materials, and uses them in its electric cars sold in Japan. The steelmaker is seeking compensation of 20 billion yen from each company and a court injunction to stop Toyota from producing electric vehicles using the Baoshan product. The nonoriented electrical steel sheet is highly functional steel. A motor can be rotated with less power by adjusting the composition and thickness of the steel.