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IP Cases & Commentary – Details

6 August 2010

Schlumberger Holdings Limited v Electromagnetic Geoservices AS [2010] EWCA Civ 819 - Person Skilled in the Art for Sufficiency and Inventive Step

Obviousness and sufficiency are two of the most important criteria for judging validity of a patent under UK and European law. Both are assessed through the eyes of the nominal ‘person skilled in the art’. In a decision handed down last week, the Court of Appeal has provided for the first time in UK or EPO case law express endorsement that the person skilled in the art for assessing obviousness should be a different person from the one used to assess sufficiency in some cases.

The European Patent Convention, and therefore also national law in the UK and other European countries, refers to the person skilled in the art in both Article 56 on obviousness: ‘An invention shall be considered as involving an inventive step if, having regard to the state of the art, it is not obvious to a person skilled in the art.’ and Article 83 on sufficiency: ‘The European patent application must disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art.’

It has long been recognised by UK and European case law that in some cases the person skilled in the art is not a single individual, but rather a team of people possessing collectively the relevant set of technical skills. This is to reflect the fact that research and development in some areas is undertaken by multi-disciplinary teams.

On 28 July 2010, the Court of Appeal, lead by Lord Justice Jacob, handed down judgment on a case - Schlumberger Holdings Limited v Electromagnetic Geoservices AS [2010] EWCA Civ 819 - overturning the decision of Justice Mann in the High Court that European Patent (UK) 1 256 019 was obvious, thus maintaining the patent. The appeal turned on whether the skilled person team necessarily had to be the same when assessing obviousness and sufficiency. Jacob's answer was an unequivocal ‘no’.

Jacob's reasoning was that obviousness was a pre-invention consideration, whereas sufficiency was a post-invention consideration, so that if the invention was a ‘game-changer’ in that it changed the technical field of the invention by introducing knowledge from a different technical field, then the team for considering sufficiency should include a member with knowledge of that different technical field, whereas the team for considering obviousness must exclude anyone from that different technical field. To avoid an absurd result, the judge also confirmed that for the patent to be non-obvious, the invention must also not be obvious from the standpoint of the excluded member alone.

Turning to the facts of the case, the invention lay in a novel use of a generically known technique. The known technique was electromagnetic mapping of the sea floor to assess the resistive structure of the underlying geology. The technique had been applied in the prior art over about 20 years to assess a variety of structures, including salt layers, deposits of volcanic rock (basalt), sedimentary rock, and methane hydrate deposits. These different structures were all identified in similar fashion by the technique, because of the fact the target layer in each case had a different resistance to the layers above and below it. The novel use claimed by the invention was to identify oil reservoirs which are generally resistive compared with the layers above them and below them.

The claimant argued this was just another routine application of the known technique which was obvious, and had also been highlighted in the literature as being possible, although not actually done in practice. The patentee argued in analogy with the famous Dyson v Hoover case RPC (2002) 465 where the skilled person was held to be prejudiced against designing a vacuum cleaner without a bag. Namely, the patentee argued that the previous uses of the technique had been in academia, not the oil industry, and that an oil-industry exploration geophysicist was the relevant skilled person. The patentee further argued that exploration geophysicists did not know much about electromagnetic surveying other than it was only practiced in academia and only worked for large-scale geological structures. The patentee's argument won the day with the judge saying that the essence of the invention was the insight that there was a solvable problem in the oil industry and that the ‘art’ known to the skilled person after the invention was made included knowledge of the electromagnetic technique which is what made the patent sufficient.

To summarise, if there is an invention in Technical Field A that applies common general knowledge from Technical Field B, then to be non-obvious and for the patent to be sufficient, the following three questions are the only ones to be asked:

  1. Is the invention obvious to Person Skilled in the Art A?
  2. Is the invention obvious to Person Skilled in the Art B?
  3. Can the invention be implemented from the patent by a joint team of A + B?

If the respective answers are no, no and yes, then the patent is non-obvious and sufficient. Specifically, it is not legitimate to ask whether the invention is obvious to a joint team of A + B.

In this particular case, definition of the technical problem was also critical to how the above questions were answered. It was accepted by all parties that the invention was obvious to a team of A + B jointly. The court formulated the technical problem in such a way that it could only be posed to Person A. If the same technical problem were posed to Person B, Person B would have said it was obvious, but the judgment reasoned that to ask the question of Person B would require hindsight and was therefore inadmissible.

The case thus breaks new ground by endorsing a disconnect between the skilled person used to assess obviousness and sufficiency as a mechanism for recognising that a patentable invention can lie purely in the identification of a problem in one technical field, the solution to which is already known in a general sense in another technical field.

At the time of writing it is still open whether the decision will be appealed to the Supreme Court, although leave to do so would be required. Moreover, the validity of the patent is still in question, since it is subject to appeal proceedings after opposition at the EPO. The UK decision actually stands in conflict with the EPO opposition decision on the same patent. The European patent was revoked by the EPO after first instance opposition proceedings for obviousness based on the same prior art as considered by the UK courts. The EPO revocation decision pre-dated the Court of Appeal hearing on this case, but was apparently ignored by the Court of Appeal in that the decision seems to make no reference to the EPO decision and no attempt to justify why the Court of Appeal has come to a different conclusion on the same facts. Only time will tell if the EPO and the UK courts will come back into alignment on the validity of this patent, or whether the EPO will follow the legal approach to the skilled person set out in the UK decision. A parallel revocation action also exists in the Netherlands which was stayed in early 2008 to wait for the EPO decision. The saga continues…

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