A court in Dusseldorf, Germany, has ruled that UK-based Molycorp Chemicals & Oxides has infringed Solvay’s patents for rare earth mixed oxides. The UK affiliate of the Colorado, US-based firm was declared to have contravened the German sections of two European patents belonging to Solvay affiliates Rhodia Operations and Rhodia Chemie.

The court found that three products of three grades of cerium containing oxides sold into Germany by Molycorp infringed at least one of Solvay’s patents. In addition, the regional court said that the proceedings filed by Molycorp in the German Federal Patent Court did not have a high chance of success. The verdict is subject to appeal, but Solvay is entitled to provisionally execute the judgment on Molycorp’s past infringement acts.

Solvay has previously won two other patent cases relating to its rare earth mixed oxides. These were both against China’s HySci Tianjin Specialty Materials which was found guilty in December 2013 of infringing the Belgian group’s patents since 2004. In addition, the Beijing High Court confirmed the validity of Solvay’s intellectual property, which HySci had tried to claim as invalid.

Rare earths mixed oxides are used in the manufacture of automotive exhaust gas catalysts to abate noxious gases, among other applications. Solvay said increasingly strict air quality standards require ever more complex formulated rare earth mixed oxides.