The German Federal Supreme Court decides on patent infringement under the doctrine of equivalence

In a decision of August 23, 2016 (X ZR 76/14 “V-shaped guiding part”) the Supreme Court again had to deal with the issue of patent infringement under the doctrine of equivalence, and has set aside the decision of the Higher Regional Court of Düsseldorf and referred the case back to this instance. The Higher Regional Court of Düsseldorf was of the opinion that a certain formulation of a feature in the claim “V-shaped guiding part” was based on an intended selection of the patentee, which does not encompass a “U-shaped guiding part” neither literally nor under the doctrine of equivalence. One of the reasons of the Higher Regional Court of Düsseldorf was that the patent, in its granted version – which in that respect had been amended in the maintained version after opposition – had reflected other shapes than a V-shaped guiding part in the description. According to the Higher Regional Court of Düsseldorf, the skilled person would understand that to be a commitment that nothing else than a V-shape is meant. The German Federal Supreme Court did not accept this claim construction: “the reasoning of the appeal court has the final result that equivalent embodiments (comparable to foreseeable equivalents according to US-American patent case law) is always excluded from the scope of protection if the patentee has understood (or could have understood) that, for a certain feature in the claim, alternatives may exist and has failed to draft the patent claim in a version that these alternatives are encompassed by the wording of the patent claim.” This is, however, not the approach of the German Federal Supreme Court. The further question – to what extent an original (and later amended) patent description is at all to be used as a tool for the claim construction – has been left open by the Federal Supreme Court. This was not decisive, because the original patent description did not mention the “U-shaped guiding part”.