In its decision on Polymer Foam II, the German Federal Supreme Court sticks to the principle that examining an inadmissible broadening has to be preceded by an interpretational examination of the patent claim, in which its meaning and especially the contribution a contestable feature will make to the performance result of the invention have to be determined. According to the court, the determination of the subject of the invention cannot be put aside with the justification that a feature is undefined and (therefore) insufficient for delimitation to the prior art.

(Patent Law Sec. 38, Sec. 14; EPC Item 69 Sec. 1; FSC X ZR 101/13 of June 9, 2015)