EPO: Implementing the most promising springboard
The European Patent Office uses the well-established problem-and-solution approach when assessing inventive step (cf. Guidelines for Examination at the EPO G.VII 5). A crucial part of this analysis is the starting point, known as the "closest prior art".
The selection of the closest prior art document is important, as it may prove easier to arrive at the claimed invention from one document than from another document. Selection of a particular document as the closest prior art generally sets the course for an assessment of inventive step.
There have been various approaches to selecting a document as the closest prior art. For many years, the Boards of Appeal at the EPO seemed to hold the opinion that there was one – and only one – document which could constitute the closest prior art. During EPO examination proceedings, and especially EPO opposition proceedings, parties before the EPO made great efforts to persuade EPO examiners that their choice of closest prior art was the correct one. Once the relevant document had been identified, arguments which started from other documents (however valid) were typically not accepted.
A change in this practice came about with the acceptance that there could be other, equally valid, problem-and-solution analyses, having different starting points. The Boards of Appeal moved to the position that a patent could be refused if it lacked inventive step on the basis of one relevant document, even if parties presented different problem-solution reasoning (cf. T308/09 and T1289/09). A lack of inventive step over a first document could not be refuted by arguments relating to a different prior art document. This developing case law was reflected in the EPO Guidelines for Examination.
EPO practice had moved away from a discussion of which document was closest to the invention. This led to opponents in EPO opposition proceedings launching multiple inventive step attacks from a range of documents, while patent proprietors had to prepare counterarguments against any conceivable starting point.
In the most recent update to the EPO Guidelines for Examination (valid from November 1 2018), this approach has been refined once again. With reference to decision T320/15, multiple inventive step attacks from multiple starting points are only allowed if the documents selected are "equally valid springboards". In particular, opposition proceedings are not seen as "a forum where the opponent can freely develop as many inventive step attacks as he wishes in the hope that one of said attacks has the chance of succeeding."
The pendulum has now swung somewhat back, and it is hoped that this lightens the burden on patent proprietors in terms of the number of inventive step arguments they need to combat in future.
Edward J Farrington