In two of the latest decisions of the Federal Court of Justice of Germany, the earlier case law regarding claim construction has been discussed. In particular, the scope of protection by way of equivalence for claims of a patent limited to a certain embodiment during examination or opposition proceedings has been clarified.
Equivalent patent infringement if only one possible embodiment is addressed by the claims
The possibility of patent infringement beyond the literal wording of a granted claim, equivalent patent infringement, is a well-established legal concept in patent litigation before German courts. The preconditions which have to be fulfilled to acknowledge equivalent patent infringement are laid down in case law, in particular in the decision “Cutting-Blade I” (file No. X ZR 168/00) of the Federal Court of Justice of Germany (FCJ).
An interesting aspect in this regard is whether there can be an equivalent infringement if the patent in suit teaches various embodiments (each of which being a solution to the technical problem underlying the patent) but only one of these embodiments is addressed by the granted claims. In an earlier decision, “Occlusion Device” (X ZR 16/09) the FCJ has denied this question for a case where each of the various embodiments was explicitly(!) mentioned in the patent in suit.
In two of the latest decisions, the FCJ has now dealt with this topic once again. In the first decision, “Pemetrexed” (X ZR 29/15), a group of compounds was mentioned in the description of the patent in suit using a generic term. All of the compounds encompassed by the generic term were indicated as a solution of the technical problem. However, only one of the various compounds encompassed by the generic term was explicitly mentioned in the patent in suit. The granted claim only referred to this specific compound. The defendant in the infringement proceedings put another compound - not addressed by the claim but encompassed by the generic term - on the market. The crucial point in this case was, therefore, whether the remaining options - not explicitly mentioned in the description but encompassed by the generic term - fall within the scope of protection by means of equivalence or not. The FCJ confirmed that, in principle, in such a case the remaining options only mentioned in the description should not fall within the scope of protection. However, this should be different if the solution according to the patent claim only serves as an example for a broader technical concept and if the skilled person is able to deduce from the wording further embodiments which correspond to this general technical concept.
This view has been confirmed in a later decision of the FCJ, V-shaped Guiding Arrangement (X ZR 76/14). In this case, a V-shaped part of a device was required according to the granted claims of the patent in suit. Other shapes were generally mentioned in the description as an alternative solution without, however, referring to another specific shape. The defendant put guiding arrangements having a U-shape on the market. Just as in the Pemetrexed-case, the FCJ came to the conclusion that a general teaching in the description enabling the person skilled in the art to find further embodiments should not be sufficient for denying equivalent patent infringement even if only one specific embodiment has been considered in the claims. Only if other specific embodiments are explicitly (!) described in the description (but not have been considered in the granted claims), equivalent patent infringement would have to be denied in line with the principles of the “Occlusion Device” decision.
In conclusion, the FCJ has “alleviated” its earlier decision “Occlusion Device” and made clear that the principles of this decision are only applicable if specific embodiments are explicitly mentioned in the description but not have been considered in the granted claims. A general mentioning of other embodiments in generic terms is, however, not enough to deny equivalent infringement. In light of this case law, care should be taken during patent prosecution to encompass all embodiments explicitly mentioned in a patent application by the granted claims.