Problems, solutions, 'tis and 'tisn't: Schlumberger on appeal

The Case of the Appeal-Proof Metaphor has just been the subject of a successful appeal, as can be seen from a perusal of Schlumberger Holdings Ltd v Electromagnetic Geoservices AS [2010] EWCA Civ 819, a decision of the Court of Appeal for England and Wales this Wednesday.

This note does not propose to discuss the merits of the appeal (neatly summarised by the IPKat here), but merely focuses on two issues that emerge from the judgment of the court, delivered by Lord Justice Jacob: (i) the application of the problem-solution approach to the question of inventive step and (ii) the role of expert witnesses who hold divergent opinions. First, obviousness:

"... the correct approach in this case is to start with the real problem faced by exploration geophysicists. Did they appreciate they had a solvable problem? One then asks whether the notional exploration geophysicist who read the cited prior art would see that the answer was to use CSEM [Controlled Source Electromagnetic surveying], or if not that, at least that CSEM had a sufficient prospect of being useful that it was worth asking a CSEM expert.

The problem must also be approached the other way round, from the point of view of the CSEM expert. Would he or she know of the exploration geophysicists' problem and, if so, would he or she appreciate that CSEM had a real prospect of being useful to solve the problem?

In short: was the marriage obvious to either notional partner?

One further approach is not necessary: that is to ask whether the notional team including both types of expert would see that CSEM would solve or stood a very good chance, of solving the problem. ...

There is danger to be avoided. There are cases where, even though you can, in retrospect, clearly see that there was a problem and articulate what it was, workers at the time did not do that. They did not say: "this is our problem. If only we had a solution to it." Instead they simply put up with things as they were. Then the essence of the invention is the insight that there was a solvable problem at all. ..."

Secondly, dealing with experts with conflicting opinions:

"I should also say something about how the court should deal with the conflicting opinions of the experts on obviousness. It is not a matter to be decided by choosing between one expert who says 'tis and one who says 'tisn't. A mere assertion of opinion is of no real value. I put it in this way [in two earlier decisions]

"But just because the opinion is admissible: it by no means follows that the court must follow it. On its own (unless uncontested) it would be "a mere bit of empty rhetoric" ... What really matters in most cases are the reasons given for the opinion. As a practical matter a well-constructed expert's report containing opinion evidence sets out the opinion and the reasons for it. If the reasons stand up the opinion does, if not, not".

I have no hesitation in repeating this. It cannot be emphasised enough. Reasons for the opinion are what really matter. It follows that it is generally not enough for the court to conclude that it accepts the opinion of one expert or the other. It too must descend into the reasons for the opinions."