Guest Post by Professor Paul Cole, Bournemouth University; European Patent Attorney, Lucas & Co, UK.
The above decision has been comprehensively reviewed in yesterday's posting by Dennis Crouch, but it is of interest because it provides a sign that the analogous art tests in Europe and in the US may not be as different as previously believed
For a primary reference, the black-letter law of the EPO as explained in the Case Law of the Boards of Appeal is that it is normally a prior art document should be selected disclosing subject-matter conceived for the same purpose or aiming at the same objective as the claimed invention and having the most relevant technical features in common, i.e. requiring the minimum of structural modifications. As regards selection of a secondary reference, T 176/84 MÖBIUS/Pencil sharpener is a widely followed appeal board decision. The primary reference concerned a known pencil sharpener and the question was whether that disclosure should be considered in combination with a second reference disclosing a securing mechanism for the slot of a savings box. It was held that a skilled person would, as well as considering the state of the art in the specific technical field of the invention, look for suggestions in neighbouring fields and/or in a broader general technical field of which the specific field was part, i.e. any field in which the same technical problem or one similar to it arose and of which the person skilled in the art should be expected to be aware.
The US analogous art test as explained in In re Bigio 381 F.3d 1320 would be accepted by most European practitioners as no more and no less than a summary of the test adopted by the EPO Appeal Boards:
Two separate tests define the scope of analogous prior art: (1) whether the art is from the same field of endeavor, regardless of the problem addressed and, (2) if the reference is not within the field of the inventor's endeavor, whether the reference still is reasonably pertinent to the particular problem with which the inventor is involved.
With this similarity in their underlying legal tests it is surprising how far the EPO and the USPTO have diverged in practice. A classic example is found in the Bigio case itself i.e. that toothbrush references are analogous art to hairbrushes, both being brushes having a handle segment and a bristle substrate segment. Judge Newman was more appreciative of the difference between a hairbrush and a toothbrush but she was in the minority. The more recent decision in Innovention Toys v MGA Entertainment (Fed Cir., Mar 21 2011) though perhaps less factually clear-cut also ruled that the art there cited was analogous.
As regards field of endeavour Klein nailed his colours firmly to the mast of nectar feeding with no less than four references to nectar in his main claim and two references to the hummingbirds, orioles and butterflies that were to receive the nectar:
21. A convenience nectar mixing device for use in preparation of sugar-water nectar for feeding hummingbirds, orioles or butterflies, said device comprising: a container that is adapted to receive water, receiving means fixed to said container, and a divider movably held by said receiving means for forming a compartment within said container, wherein said compartment has a volume that is proportionately less than a volume of said container, by a ratio established for the formulation of sugar-water nectar for hummingbirds, orioles or butterflies, wherein said compartment is adapted to receive sugar, and wherein removal of said divider from said receiving means allows mixing of said sugar and water to occur to provide said sugar-water nectar.
The objection as set out in the government's appeal brief was that the art taught multiple examples of containers with compartments separated by removable dividers, that Mr Klein was not entitled to a patent just because he sought to put these containers to a particular use to which these prior art containers had not been put and that substantial evidence supported the Board's conclusion that the prior art containers would have commended themselves to someone like Klein who faced the problem of finding a container capable of being divided into separate compartments. However, the government's contention that the problem was simply one of "compartment separation" did not resonate with the CAFC. They dismissed this broadening from the narrower nectar-related formulation of the problem found by the Board for procedural reasons. It is difficult to see what basis there could be for broadening the problem in this way except for wilful blindness as to the nature of the invention and creation of an improper hindsight mosaic of prior art. However, it seems doubtful that Klein would have succeeded on this issue but for the forthright way in which he had defined his field of endeavour in his claim.
In the previous posting it has been noted that Klein's narrow "purpose" of the invention goes against common patent attorney practice because the narrow purpose can also lead courts to narrow the claim scope during claim construction and in their analysis of infringement under the doctrine of equivalents. Attorneys may want to rethink that approach in light of this case. A European practitioner would say "amen" to that. Klein was in the business of jugs for nectar mixing and nothing else. There was no mileage for him in extending his claim scope into unrelated and wholly speculative fields from which he could not expect ever to receive revenue, but which would expose him to unknown and potentially fatal prior art.
The USPTO's decision to select e.g. an accounting drawer as starting point prior art seems to a European practitioner to be putting the cart before the horse. European practice follows the approach of the Irish farmer asked by an English visitor lost in the back roads of Kerry: "Can you direct me to Dublin?" He replied: "If I wanted to go to Dublin, I definitely wouldn't start from here!" Arguably the natural starting point for development of the invention was the nectar and how to dispense its ingredients accurately. That the drawer was an unnatural starting point is supported by the reasoning in EPO Appeal Board in T 570/91 AE PLC/Pistons which with modification to follow the facts in the present case would read as follows:
"If … a person skilled in the art prefers and decides to start from a specific accounting drawer, he can further develop that drawer but at the end of that development the normal result will still be an accounting drawer and not a nectar mixing device."
In its opinion the CAFC adopted a similar approach to AE PLC, following a dictum in In re Clay 966 F.2d 659 that "If [a reference]is directed to a different purpose the inventor would accordingly have had less motivation or occasion to consider it." None of the references of this type showed a partitioned container that was adapted to receive water or contain it long enough to be able to prepare different ratios in the different compartments, and the Board's finding that the five references at issue were analogous art was not supported by substantial evidence.
As to the merits of the case, useful guidance is given in the opinion of Jacob L.J. in Schlumberger v Electromagnetic Geoservices  EWCA Civ 819 where he was grappling with the same problem of a combination of prior art A and B in dissimilar arts and asked in what circumstances a marriage of skills in dissimilar arts could be obvious to either notional partner. He observed:
"In the case of obviousness in view of the state of the art, a key question is generally "what problem was the patentee trying to solve?" That leads one in turn to consider the art in which the problem in fact lay. It is the notional team in that art which is the relevant team making up the person skilled in the art. If it would be obvious to that team to bring in different expertise, then the invention will nonetheless be obvious. Likewise if the possessor of the "extra expertise" would himself know of the other team's problem. But if it would not be obvious to either of the notional persons or teams alone and not obvious to either sort of team to bring in the other, then the invention cannot fairly be said to be obvious. As it was put in argument before us the possessors of the different skills need to be in the same room and the team with the problem must have some reason for telling the team who could solve it what the problem is."
The value of the insight in Schlumberger is amply demonstrated by the fact pattern in the present case, although admittedly the invention discussed in Schlumberger lies at the opposite end of the scale in terms of commercial importance and technical difficulty. In the present case the state of the art had not progressed beyond retailers selling nectar feeding equipment and giving advice as to the ratio of sugar to water for the various creatures that it was desired to feed. On the evidence of what was said in the specification customers had been confused and forgetful for years, but until Mr Klein's invention nobody had identified this as a technical problem, still less thought of looking in the receptacle art for a potential solution. In the words of Jacob L.J. in Schlumberger:
"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."
If the less plausible starting point in the receptacle art is taken as the starting point, what realistic prospect was there of a designer of receptacles with removable dividers e.g. for business or accounting purposes realising that there was a problem associated with nectar feeding that could be solved by making the receptacle water-tight and adapting the divider positions for sugar and water to make nectar?
On either view the objection sustained by the Board was based on impermissible hindsight and was correctly reversed by the CAFC. The nectar feeding people and the receptacle designers would never have got engaged, still less married, if they had not somehow been introduced, and there was no straightforward mechanism in the prior art for such an introduction to have been made.
The mechanical examples in the MPEP at 2141.01(a) all reflect cases where the government view as to how the analogous art test should be applied succeeded. Klein provides a counter-example of applicant success that it is hoped will soon find its way into MPEP. As regards Bigio, while that decision can usefully be cited for the rule that it affirms, it is submitted that it is an outlier which while possibly correct on its special facts should not be held up to examiners as a good way of arguing the normal run of cases.