Wednesday, 20 April 2016

Instructing the Expert - American Science & Engineering Inc v Rapiscan

One of the key differences between the UK patent litigation system and the continental system is the role of expert evidence, in particular when it comes to inventive step. German courts consider obviousness to be a question of law, the role of the experts being only to shed light on the knowledge and mindset of the the person skilled in the art at the priority date. Finding a compromise between both of these positions will surely be a crucial task to tackle in the first decisions of the UPC.

In the decision American Science & Engineering Inc v Rapiscan Systems Ltd [2016] EWHC 756 (Pat) (11 April 2016)  , justice Arnold shares the following general comments on how to instruct the expert:

General comments on the expert evidence
109. Each party contends that the other party instructed its expert to ask himself the wrong question. Both sides' solicitors proceeded in a carefully structured manner by first asking their expert to consider the person skilled in the art and the common general knowledge, then to consider the prior art relied upon by Rapiscan and only then to consider the Patent. The difference between them was that AS&E's solicitors asked Dr Bjorkholm to consider obvious developments of the prior art before showing him the Patent, whereas Rapiscan's solicitors only asked Dr Lanza to consider the question of obviousness after they had shown him the Patent.
110. In my view there is force in the criticisms which each side levels at the other's approach. The approach adopted by AS&E's solicitors had the advantage that it enabled Dr Bjorkholm to consider obvious developments of the prior art free from knowledge of the Patent; but it meant that he never addressed in his reports the question of whether the differences between Swift and the claimed invention constituted steps which would have been obvious to the person skilled in the art. The mere fact that a step did not occur to Dr Bjorkholm when reviewing the prior art was not sufficient to exclude the possibility that he might agree that it was obvious if asked. Unlike the person skilled in art, real people sometimes miss the obvious.
111. The approach adopted by Rapiscan's solicitors avoided that difficulty. The problem is that, whereas the correct question is whether, viewed without any knowledge of the claimed invention, the differences constituted steps which would be obvious, Dr Lanza expressed his understanding of the question he had been asked to consider without referring to the need to exclude knowledge of the claimed invention. Moreover, this does not appear to have been an artefact of the drafting of the report. On the contrary, Dr Lanza confirmed in cross-examination that his approach had been to consider obviousness as if the skilled person had been shown the claims and asked if they were obvious. Thus Dr Lanza does not appear to have understood the importance of trying to avoid hindsight.


MaxDrei said...

Michael, below I copy a Comment I just made on the IPKat blog. I thought it might prompt a comment from you in reply, perhaps:

Not too late for a comment, I hope, given that there are more recent posts on this case in other blogs, that my comment below is inspired by the piece in the PatLit blog and that it concerns the role of contemporaneous witness evidence in assessing what was obvious back them years ago, at the date of the claim.

In this case, the patent owner witholds from its expert any knowledge of the patent and enquires of him what would have been obvious. Not surprisingly (to me anyway) the expert comes up with a thousand obvious tweaks but fails to identify the "small step" that would produce the technical feature combination of the claim at bar.

Meanwhile the accused infringer shows its expert the patent and enquires whether the claimed feature combination was at the time obvious. Not surprisingly (at least to me) the expert concludes that it was.

Talk about setting things up to get the answer you want and need!

How to do obviousness fairly, asking your expert but without taint of hindsight? The judge doesn't know. Of course he doesn't. It's not do-able.

Me, I prefer doing obviousness using a TSM approach. You know, the one the EPO uses. That at least is fair and free of hindsight. There was in this case a hint or suggestion, indeed from the patent owner, but the judge thought it (unsupported by evidence of an industry-wide trend to covert inspection activity) not quite concrete enough to have rendered the claim obvious. Me too.

And BTW, I think it a bit rich (to say the least) that those who disparage EPO-PSA, dismissing it as tainted by hindsight, are the very ones who dare to suggest that the way to drive out the demon hindsight is to decide it all on the basis of contemporaneous witness evidence. They are pulling our legs aren't they?

Perhaps those who know more about deposing technical experts will put me straight. Hope so.

Michael Thesen said...

My remark in the introduction of this piece touches a very profound difference between the German Law approach and the Common Law approach. In a nutshell, the German approach is as follows: Patent claims define what is forbidden and therefore has the character statutory law ("Rechtsnormcharakter"). Everything related to the interpretation and obviousness is therefore a question of law and not a question of fact.

This has various consequences: Questions of fact cannot be scrutinized in the Revision instance and the right to review facts in the appeal instance is limited. Questions of law have to be answered autonomously ("eigenverantwortlich") by the judge in any instance and cannot be proven or disproven by witnesses, expert evidence or other evidence.

The taking of evidence (including expert evidence) only serves to shed light onto the factual circumstances (e.g. education and knowledge of the POSITA at the priority date or the like) and the German judge would simply not ask the expert if he thinks that something would have been obvious or not - just as he would never ask another witness how he would decide on the merits of the case if the witness were the judge.

As long as the questions are limited to the "historical facts" there is no problem of hindsight. This problem starts where the expert is asked to draw conclusions from the facts. These conclusions risk to be tainted by hindsight knowledge of the patent (and of the technical development since the filing date).

MaxDrei said...

Herr Thesen, I'm not sure the differences are as you suppose. In England, the question Obvious Y/N is a question of law based on foundations of fact. So, no different than in Germany, I would say.

So if we can summarise:

Germany: Obvious. Because I'm the judge and I say so.

England: Obvious. Because I'm the judge and the preponderance of witness evidence on the facts forces me to that conclusion.

EPO: Obvious. Because we are the judge of that, basing ourselves on the evidence of documents written before the date of the claim.

Is that fair, or a travesty? What do you think?