The Higher Regional Court of Düsseldorf has already had two opportunities this year to apply the requirements relevant for the question of objectively equal effect in the examination of an equivalent patent infringement, whichwere concretised by the BGH decision Kranarm (judgement of 17 November 2020, file no. X ZR 132/18) (judgement of 18 March 2021, case no. 2 U 18/19 – lifting column and v. 10 June 2021, case no. 2 U 19/19 – pipe cleaning device).
In Germany – and in other countries – the recognised principle of patent law has long been that a patent can be infringed not only literally, but also by equivalent means. The legal examination of an equivalent patent infringement in Germany is based on the three-step test developed by the case law of the Federal Court of Justice, so-called cutting blade questions. Accordingly, the prerequisites for the existence of an equivalent patent infringement are (1) equal effect, (2) detectability and (3) equivalence.
Decisions of the Higher Regional Court of Düsseldorf
In agreement with and with explicit reference to the Kranam decision of the Federal Court of Justice (BGH), the Higher Regional Court of Düsseldorf states that an embodiment that has a deviating design, as regards a feature provided for in the patent claim, can not only fall within the scope of protection of that patent if it achieves the intended effects according to the invention and without any limitation. Rather, it could also suffice for an equal effect if the intended effect according to the patent claim is achieved by modified means to only a limited extent. Under the aspect of an appropriate reward for the inventor, inclusion in the scope of protection of a patent could be appropriate, even if the intended effects according to the invention were essentially achieved, i.e. to a practically still considerable extent. For this purpose, the intended effect according to the patent and a weighting of the deficiencies found in the challenged embodiments onthis basis were decisive.
Taking these standards into account, the Higher Regional Court of Düsseldorf affirmed an equal effect in the decision of 18 March 2021, but denied it in the decision of 10 June 2021.
As a result, taking into account the new case law of the Federal Court of Justice, which the Higher Regional Court of Düsseldorf follows in the above-mentioned decisions, it can be stated that a modified embodiment can have an equal effect if it also achieves precisely the effect which the feature not literally realised is intended to achieve. It is sufficient if the effect is essentially achieved, i.e. to a limited but at least still practically significant extent.