Should we bother with experts?

Should we bother with experts?

This article, thankfully, is nothing to do with the now infamous quote of Michael Gove MP,  that people have “had enough of experts” and instead looks at how the European Patent Office (EPO) handles submissions from technical experts, and what contribution having a technical expert on your side really makes at the EPO.  

The right to be heard

The EPO has a fundamental principle called the right to be heard. This means that decisions of the EPO may only be based on grounds or evidence which the parties concerned have had an opportunity to present their comments on, and also gives parties the right to use a technical expert in their written or oral submissions to the EPO.  
It can be tempting to think that having a technical expert on your side will add a degree of prestige and credibility to your position. After all, if the leading expert in the field thinks that your invention was not obvious, then the invention must surely satisfy the requirements for inventive step, right? Unfortunately, the EPO rarely agrees.   

Falling on deaf ears

Firstly, the EPO recognises that any such expert will have been selected (and probably paid) by a party to support their view, and are therefore not considered to provide an unbiased opinion. In some countries, such as Italy, the patent court can provide “approved” technical experts to try and get around this. However, given that the EPO handles a vast number of inventions in hundreds of different technical fields and three different languages, it is unlikely that the EPO could adopt a similar approach.     

More importantly, however, is that the EPO uses the “problem-and-solution” approach to determine whether a claim has an inventive step. This relies heavily on the so-called “person skilled in the art” and whether they would have arrived at an invention from the prior art. The person skilled in the art is a fictional person who has average ability and has access to all documents in his/her technical field, irrespective of when they were published and the language they were published in. However, the person skilled in the art does not have any inventive capacity. In many cases, the person skilled in the art can be thought of in practical terms as a technician with access to a vast library and plenty of time to view it!  

In contrast, any technical expert will, by their very nature, have specialist knowledge in one particular area and cannot be said to have “average” knowledge of a subject. However, even the most well-informed technical expert is unlikely to be familiar with all possible documents in his or her subject.  Therefore, the use of a technical expert in EPO proceedings is not likely to be seen as suitable in supporting an argument for inventive step, since any such expert is clearly not the person skilled in the art. Since the same definition of the person skilled in the art is used for the assessment of clarity and sufficiency, the same conclusion has to be drawn here too.  
In fact, because a technical expert is obviously not the person skilled in the art, the EPO may not admit their evidence into a case. As an example, we were recently involved in a hearing before the Opposition Division of the EPO in which the other side flew in a technical expert from Australia. Much to the Opponent’s annoyance, he was not allowed to speak, precisely because he was not the person skilled in the art. 

So, is it ever worth using an expert?

While the EPO is not likely to give much weight to inventive step submissions made by a technical expert (for the reasons above), having a technical expert on hand can be very valuable, as they can help to ensure that your technical arguments are on point and that you have a clear understanding of the prior art. It has been our experience that the winning side in contentious proceedings is usually that which has the best understanding of the technology, and this is where the help of a technical expert can be invaluable.  Further, use of a technical expert can be valuable, in writing, to describe why one or more of the other parties, or the EPO has erred in a technical understanding of, for example, the prior art.  Usually, any such description would need also to reply on technical evidence, such as a text book or prior art.


It is our view that technical experts do have value during EPO proceedings, but more as a resource, and less as a declarant or as a spokesperson. If you find yourself in a situation where your only option for an inventive step argument seems to be relying on a declaration from a technical expert, it might be more helpful to take a step back, review the position using the ‘problem-and-solution’ approach and see whether your technical expert can be deployed elsewhere to more effect.


For further information, please contact Victoria Barker or your usual Kilburn & Strode advisor.

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