The law
24.It was common ground that the issue of inventive step should be assessed using the approach explained in Pozzoli SpA v BDMO SA [2007] EWCA Civ 588; [2008] RPC 37, at [23]. 25.Mr Aikens drew my attention to the judgment of Lewison J in Ivax Pharmaceuticals UK Ltd v Akzo Nobel BV [2006] EWHC 1089 Ch; [2007] RPC 3, on the approach to inventive step in a heavily regulated field such as the one in the present case. Lewison J summarised the effect of the earlier judgment of Jacob J at first instance in Richardson-Vicks Inc’s Patent [1995] RPC 568 and that of Aldous LJ on appeal, [1997] RPC 888. Like Ivax, Richardson-Vicks was concerned with pharmaceutical products. Lewison J said: “It seems to me, therefore, that obstacles to regulatory approval of pharmaceutical products are not relevant obstacles to an obviousness attack. It is also worth drawing attention to the clear distinction drawn by Aldous LJ between obstacles to manufacture on the one hand, and obstacles to lawful sale on the other. Obstacles to lawful sale are not relevant to obviousness.” 26.Mr Keay relied on this passage in the judgment of Kitchin J in Eli Lilly and Co v Human Genome Sciences, Inc [2008] EWHC 1903 (Pat); [2008] RPC 29, at [295]: “I accept that the skilled person must be deemed to consider any piece of prior art properly and in that sense with interest. This emerges clearly from the decision of the Court of Appeal in Asahi Medical Co Ltd v Macopharma (UK) Ltd [2002] EWCA Civ 466 and is necessary to prevent a patent from depriving the public of their right or make or do anything which is merely an obvious modification of what has been done or published before. But the law does not deem the skilled person to assume the prior art has any relevance to the problem he is addressing or require him to take it forward. Having considered it, he may conclude that it is simply not a worthwhile starting point and so put it to one side.” 27.The facts in Eli Lilly were that the prior art in question was a polynucleotide sequence in a database which was accessible to the public at the priority date, but it had not been characterised and was indistinguishable from 390,000 other sequences of that type in a database. Kitchin J rejected the hypothesis that the skilled person would start with the particular sequence relied on. However, I do not understand him to have meant that the usual approach of assuming that the prior art has been drawn to the attention of the skilled person who, at the relevant time, would have considered it carefully, was being cast aside or that there can be exceptions to such an approach. His point, as I understand it, was that by picking out the particular sequence in question as the cited prior art, the party seeking to revoke the patent had, in effect, wrongly ensured that the bulk of the hypothetical work of the skilled person in assessing obviousness had already been done. Or, to put it another way, the key qualities of the particular nucleotide sequence were not known at the relevant date and therefore that sequence was not individually part of the state of the art. One way of adopting the usual approach, therefore, was to treat all 390,000 uncharacterised sequences as the starting point. The hypothesis would have been that all these sequences were put under the nose of the skilled person. The question was whether it was obvious to take the step from there to the claimed invention. For this reason, Kitchin J considered obviousness by reference to, among other things, evidence on screening polynucleotide sequences. 28.It is clear from the passage from Eli Lilly just quoted that whether the skilled person takes the view that an item of prior art is a promising or unpromising solution to the problem, he or she will consider it with exactly the same care and interest. 29.Moving away from the particular facts of Eli Lilly, it is possible for the subject matter of the prior art to be too remote from the nature of the problem to suggest the claimed solution to the skilled person. Sometimes such prior art is characterised as being not a worthwhile starting point. But this sort of remoteness is really just one of many alternative reasons why a skilled person may, having carefully considered the prior art, fail to spot the invention. 30.In the present case it was said of one of the cited items of prior art that the skilled person would have thought that implementing its content would result in making a product that was dangerous to users and that therefore the prior art would have been of no interest as a starting point. I think that characterising prior art as a good or bad starting point can be a distraction. Whatever the prior art may be, the skilled person is invariably required to start with it in the sense that he or she is deemed to have considered it carefully. Having done so, the skilled person either will or will not find the invention in suit technically obvious. 31.The perception of a dangerous outcome might be relevant on certain facts. To take an example, a line of investigation may not be pursued by the skilled person because of expected dangers involved and this might make a difference to the obviousness of the end-product of such an investigation. However, such circumstances must be distinguished from a situation in which the skilled person believes a variant of the prior art to be technically obvious but of limited or no commercial value because the result may be dangerous or otherwise unattractive to users. Such unattractive qualities would not make the variant any less obvious from a technical standpoint. The unattractive qualities may affect whether the variant falls within a claim, but that is a separate matter.