Monday, 29 March 2010

EQE 2010: claim 1, 54(2)

With the new DeltaPatents website online we can start working at the content again. As promised, I will say something about the 54(2) attack on claim 1 of last month's EQE exam.

A 54(2) attack may either use novelty or inventive step. Before selecting a closest prior art or novelty destroying embodiment we first determine the claimed object, i.e. a liquid dispenser with a gaseous propellant. Then we try to find this object in the available 54(2) documents (A2, A3, A5). A2 is about a gas dispenser (first line of [0001]), A3 uses an aluminium bottle (first line of [0001]) and in A5 the trapping material is not coated on the wall ([0005] in combination with item 56 in the figure). It is clear that we cannot do a novelty attack and have to select a closest prior art.

A2 is not suitable as closest prior art, because it does not have the claimed object. The apparatus dispenses gas instead of liquid. That's not the type of apparatus the skilled person wants to improve. Starting from A3, the skilled person would have to replace the aluminium bottle by a plastic one. Usually, the exam committee is of the opinion that such a change of material for the main object would require so much effort that the skilled person would not start from such a prior art. Additionally, A3 misses the use of a dip tube and might thus not be the ideal starting point for an inventive step attack. A5 discloses a liquid dispenser and only misses the fact that the trapping material is coated on the wall. A5 clearly is the closest prior art.

Now we know the closest prior art and the missing feature, we have to formulate an objective technical problem. For that we use Annex 1. Annex 1 describes the advantageous effect of the missing feature in [0008]. The coating avoids clogging of the dip tube.

We know that the missing feature must be in A2 or A3. In those documents, we start looking for the feature and for the missing effect. A2, [0003] describes gas-permeable porous material 25 which functions as a trapping material and 'must adhere to the inside of the wall of the can in order to avoid clogging of the inlet by loose parts of it'. Of course A3 does not have anything useful and the attack will thus be A5+A2.

With this information we should be able to complete our inventive step attack. We already have the missing feature and an incentive to combine. Still missing are an argument for reading A2 (neighbouring field and use of trapping material), a description of the combination that the skilled person would actually make and an optional discussion on compatibility. With respect to the latter issue, it might be required to say something about the compatibility of the coating with the plastic container of A5, because there is some interesting information about that in [0004] of A2.

1 comment:

  1. Question from a visitor: "Why start with A5 which offers another solution to the technical problem?"

    Let's start with saying that we are not the exam committee. This is just an opinion of a tutor who tried to make the exam before the official model solution is provided. My preferred attack may not be the (only) one which will turn out to be worth a substantive amount of marks.

    Back to the question. The fact that A5 does already have a similar solution to a similar problem makes it a very suitable starting point for an inventive step attack. It means that A5 is very close. If we compare A5 to the prior art admitted in A1, we see that A5 has all features of the admitted prior art and in addition the use of plastic. It is in the right technical field, fulfils similar purposes and has more features in common.

    In the problem solution approach, the problem does not have to be apparent from or mentioned in the document describing the closest prior art. Sometimes it is, but usually it isn't. The objective technical problem is defined by comparing the closest prior art and the claimed invention and by determining the effect of the missing feature(s). Usually (practically always in the exam) the granted patent (A1) describes some advantageous effects of the missing feature. If this effect is not yet obtained in the closest prior art, we use normal problem solution. If all mentioned advantageous effects are already obtained in the closest prior art, but in a different way, we do an alternative attack which is a special flavour of problem solution.

    In this example, A5 already has the gas trapping effect of the claimed trapping material. A5 does however not have the effect of avoiding clogging of the dip tube. As a fictitious skilled person we define the objective problem as ‘how to avoid clogging’. As you already know, the answer is in A2.