Two decisions handed down from the English appeal courts suggest that the manner in which the "obvious to try" test is being applied is raising the bar for patent challengers in demonstrating the skilled person (or team) would have arrived at the impugned invention through obvious routes given certain prior art.

The first case of Apimed Medical Honey Limited v Brightwake Limited [2012] EWCA Civ 5 was handed down in January and concerned an appeal from the judgment of the Patents County Court that the patent was invalid. The appeal was unopposed in the sense that Brightwake had withdrawn from the case because the parties had settled following a finding of non-infringement in the lower court. Hence Apimed appealed only on the invalidity of its patent and the Comptroller of the IPO opposed through the Treasury Solicitor because the case raised sufficiently important issues (namely the undesirability of invalid patents being returned to the register for want of opposition) for the Comptroller to seek judicial clarification.

The main points in issue were:

  1. Whether the judge had correctly identified the patent's contribution over the prior art;
  2. Whether a finding of "obvious over the common general knowledge" could be justified;
  3. Whether the comptroller would be permitted to raise a new novelty argument.

On these points, the first two flow in sequence. First, the Court of Appeal found that the judge had failed to identify the true invention as compared to the cited prior art. The invention itself required the use of an alginate gelling agent to thicken honey such that it could be used as a putty or rolled into a sheet to dress wounds, i.e. it did away with the need for dressings. When compared with the prior art that described the use of alginate/gauze dressings the true invention was to remove the need for a dressing, not the particular agents to use within a dressing. Having corrected the judge's analysis of the differences between the invention and the prior art the Court overturned his finding of obviousness.

The Court then turned to the finding of "obvious over the common general knowledge". In respect of this the Court said:

"It is well established that an obviousness argument based upon the common general knowledge alone must be treated with caution because it is unencumbered with any detail which might point to non-obviousness and is particularly likely to be tainted with the impermissible use of hindsight."

As one might expect, having thus opened its analysis of this part of the judge's findings, the Court found that this part of the judgment was also unsound and overturned this finding of obviousness.

As to the new arguments that the Comptroller sought to bring into the appeal, the Court said that they were not before the court at first instance, had not been developed in evidence, and raised technical issues which would be impossible to resolve in the appeal. The Court therefore refused to permit the Comptroller to raise this new point.

The second case that we wish to bring to the attention of readers is Gedeon Richter plc v Bayer Schering Pharma AG [2012] EWCA Civ 235. This is another decision of the Court of Appeal dealing with obviousness. Bayer is the proprietor of a number of patents directed at formulations of birth control medications. Two patents were in issue at trial. The judge had found the main claims of one of the patents invalid for obviousness but permitted the patentee to amend the patent to delete the invalid claims. The second patent, also in amended form, was held to be valid. The appeal went forward on the findings of non-obviousness of the amended claims and also that the patents contained added matter. We will focus on the first part of the appeal.

Gedeon Richter put forward the challenge on appeal that the skilled team would have read together two publications separated in time by over 10 years and where the earliest paper was published over 15 years before the priority date of the two patents challenged. The Court noted that it was "a matter of trite law" that the earlier before the priority date is the prior art cited for obviousness, the harder it is to prove the obviousness case. Further, the case on obviousness was complicated because the later paper of the two Gedeon Richter argued that the skilled person would combine, concerned a substance that was not one of the actives in the patent claim, was published in a little read journal and did not provide formulation details of the active it concerned. The combination of papers was critical to Gedeon Richter's case because following only the earlier paper would have led to the skilled person undertaking in vitro tests and becoming discouraged, in effect there was a "lion in the path" when following the accepted formulation prior art.

Despite the apparent difficulties in this case, the main argument was that the deficiencies in the later prior art from a formulation standpoint was tempered by the fact that the skilled team in this case did not only contain formulators, but medicinal chemists and biochemists too and they would turn up the later paper in a publication search and bring it to the attention of the formulators. The Court rejected this (noting, for example, that Gideon Richter had not called a medicinal chemist to address the point).

Gedeon Richter also ran a variant of this, an "obvious to try" argument based on these two papers. The Court again rejected this. Although the judge had accepted that the prior art might have led the skilled team to consider that the "drug might survive in the final formulation", this was not good enough. In the view of the Court of Appeal, the judge's analysis placed the result of the invention closer to "not impossible" than "obvious". As further words of caution, the Court of Appeal took into account other evidence as proof of non-obviousness. The evidence of how long it took to arrive at the invention was considered telling and the fact that it is still not known why the in vivo results with the drugs differ from the in vitro results (which the Court found would have discouraged the skilled team from proceeding any further) strongly suggested that the invention was not obvious because the result could not have been predicted.

Both cases represent cautionary tales for parties wishing to run obviousness cases in the UK. Further, although secondary evidence alone is probably not good enough to win a case for a patentee, for the Court of Appeal in the Bayer case it was clearly a useful "common sense" check that they, and the judge at first instance, had analysed the inventiveness of the patent in the correct way.

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