“Thickening polymer I” and “Thickening polymer II”, Bundesgerichtshof, Germany, 5 May 2015 and 7 July 2015. Case No's X ZR 60/13 and X ZB 4/14
The Federal Patent Court Bundesgerichtshof decided in its decision “Verdickerpolymer I” (Thickening polymer I, docket n° X ZR 60/13) that in order to destroy novelty of a patent, it is not necessary that all possible combinations of the claim were known in the state of the art. The patent claimed a composition of an associative thickener, a surfactant and water. The associative thickener should be selected from polyurethanes, polyesters, modified cellulosics, poIyester-urethanes, polyether-alpha olefins and polyether-polyols; the surfactant had to be selected from anionic and non-ionic surfactants and mixtures thereof, the rest being water.
In the state of the art, there was known a composition of a polyurethane thickener and a non-ionic surfactant, in the amounts claimed in patent claim 1, with the remainder being water. The patentee argued that only one possible combination falling under the patent claim was known in the state of the art, whereas all other possible combinations were not known. However, he did not disclaim a combination of a polyurethane, a non-ionic surfactant and water.