The Guidelines for Examination at the EPO have been significantly revised with the updated version due to come into force on 1st November 2018. The revisions relate to Computer Implemented Inventions, Inventive Step assessment in Opposition, Unity and more.

While, as the name suggests, the Guidelines do not provide binding precedence for the EPO, they do set out the day-to-day practice to be adopted by examiners. Familiarity with the Guidelines is important for a European Patent Attorney: the Guidelines are the best tool we have for understanding how an examiner is likely to approach an issue and an argument solidly based on their content is unlikely to be dismissed.

In a series of articles, we examine the changes, and how these may impact practice.

Part G, VII-5.1

The EPO's problem-solution approach for assessing inventive step of a patent includes determining the "closest prior art" as the first of a three stage approach. The obviousness of the claimed invention is then determined starting from this document. The closest prior art, therefore, plays a pivotal role in the assessment of inventive step at the EPO.

The current revision to the relevant section of the EPO Guidelines aims to curb Opponents arguing that several documents can be considered the closest prior art and making several inventive step attacks, each starting from a different document. Understandably, Opposition Divisions tend to see such a scatter gun approach as procedurally inefficient, as well as creating more work to review and make a decision on these attacks.

The Guidelines therefore now state that application of the problem-solution approach starting from more than one prior art document as the closest prior art is only required where it has been convincingly shown that these documents are equally valid starting points.

In principle, this is a noble attempt to focus opposition proceedings and the avoid many of the weak attacks from Opponents. However, it is not clear that this addition will provide much procedural efficiency. In particular, the Guidelines imply that the Opposition Division need not consider inventive step attacks from close (but not the closest) prior art documents. We can therefore anticipate that arguments over the selection of the closest prior art may be more detailed both in written and oral proceedings.

It is also not clear whether or not the Opposition Division will need to deliberate before giving a decision on the selection of the closest prior art before moving on to discuss inventive step at oral proceedings. If such a decision goes against one of the parties, then the issue is likely to simply be pushed up to the Boards of Appeal. There is little point in improving first instance proceedings if the issues merely cause further delays at the Appeal stage.
It seems likely that the Opposition Division will want all Opponents in a multiple-Opponent Opposition to start from the same prior art document as closest prior art. Some Opponents may feel that such a restriction is a violation of their right to be heard, particularly if that Opponent had not cited the chosen closest prior art.

Practice points

The revision shouldn't significantly change Opposition practice. It has always been best practice to put forward most prominently the strongest arguments, especially at oral proceedings. The revision should also not deter Opponents from arguing from two different starting points if they are believed to be equally valid starting points. However, Patentees and Opponents should expect to discuss and potentially argue the selection of the closest prior art in more detail from now.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.