Most readers will be aware of the so-called “all elements” test, whereby patent infringement is normally discarded unless the allegedly infringing device or process reproduces each and every element of the claim.

The “all elements” test contrasts with the so-called “essentiality” test. According to this test, there can still be infringement if an element of the claim is missing in the allegedly infringing device or process, as long as that precise element is not “essential” to put the invention into practice. For example, the German Supreme Court found in the “Air-Breathing Hose” judgment that the absence of an element would only exclude infringement if the patent owner had described such element as an essential feature of the invention.  A decision of 30 December 2016 from Commercial Court number 1 of Barcelona has sparked the debate regarding whether the “essentiality” test is also making inroads in Spain. In this recent case, the Court ordered a preliminary injunction against a Spanish company that was marketing a device to spray liquids. According to the Court, the fact that one of the elements of the claim was missing did not rule out direct patent infringement. In particular, the Court wrote that «In relation to the characteristic (1c) “and a spray nozzle (4) for dispensing fluid from within the liner 13”, the BPS system as such does not include the spray nozzle which, we agree with the applicant, does not exclude a case of direct patent infringement insofar as the BPS system reproduces the essential elements of the independent claim of the same (doctrine of the Vileda case of the Barcelona Court of Appeal).»

If the criterion expressed in this decision is confirmed by the Barcelona Court of Appeal and / or by the Supreme Court in the main proceedings, it could mean that the “essentiality” test is here to stay.


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One comment

  1. It is interesting to see the development of the “essentiality test”, or “three steps test” when it comes to infringement. Whether it will make inroads in Spain will have to be seen.

    It is clear that the “all elements” test is much easier to apply, as all features have to be taken into account. No interpretation whether a feature can be dispensed with when deciding on infringement. Whether this principle should be applied indistinctly is a different matter, hence the use of the “essentiality test” even when it comes to infringement.

    When it comes to the “essentiality test” in proceedings before the EPO, i.e. grant or opposition, it rather seems that the “essentiality test” may be on the way out, at least under this name.

    Definition of the “essentiality test”:
    What does the “essentiality test” or the test according to T 331/87 say?
    The replacement or removal of a feature from a claim may not violate Article 123(2) EPC provided the skilled person would directly and unambiguously recognise that
    – (1) the feature was not explained as essential in the disclosure,
    – (2) it is not, as such, indispensable for the function of the invention in the light of the technical problem it serves to solve, and
    – (3) the replacement or removal requires no real modification of other features to compensate for the change
    If one wants to grab the subtlety of the essential test, he is invited to look at Paper B 2000 of the EQE.

    Critical view of some Boards re “the essentiality test”:
    In a decision of the beginning of the year, T 1852/13, the Board has expressed strong reservations about the “essentiality test”, which I defined in the Guidelines under H-V, 3.1. By the way the name “essentiality test” has disappeared from the Guidelines (before it disappears completely?).

    The Board found a number of decisions having applied this test, but also found decisions which criticised it. In T 1852/13, the Board considered that this test should not be applied any longer!

    The main reason brought forward is that in G 2/98 (Validity of priority), that a distinction between essential and non-essential features should not be applied when it comes to decide whether priority is valid or not. The same standard has to apply as when deciding on novelty or added subject-matter. In other words the valid standard is the one defined in G 2/10. The link with G 2/98 had already been made in one of the decisions criticising the “essentiality test”, T 2311/10.
    In T 2311/10 the Board held, with reason, that the problem to be solved in step 2 cannot be the objective problem that results from the differences with the closest prior art. If this were the case, the application of Art 123 (2) would depend on the prior art, which cannot be the case.

    Does the name of the test really matter?
    On the other hand, defining whether a feature is essential or not may seem arbitrary.
    What appears important to consider is what has been disclosed in which context. A feature is in principle embedded in a given context. If a feature can be removed from a claim without changing the context of the whole claim, it means that the feature does not contribute to said context.
    It then boils down to deciding of deciding whether the context and the feature are inextricably linked. If the answer is positive, then a feature cannot be removed without adding subject-matter. If the answer is negative, the feature and the context are not inextricably linked then there is no added subject-matter when deleting the feature. Translated into “old” terms context is an “essential” feature and the feature that can be deleted is a “non-essential” feature.

    However, without naming it so, the “essentiality test” remains a good instrument for deciding whether a feature can be deleted or not. Let’s say that if the result of a process depends on the temperature and the pressure, neither one of those two features can be deleted, as they are both inextricably linked. If the result of a process is dependent of the temperature, then the temperature cannot be deleted, but the pressure, and vice versa. It means that either the pressure or the temperature is not inextricably linked with the process. In other words, the context is the process and the “essential” feature can be either the temperature or the pressure, or both.

    When it comes to a combination of claims as filed or granted, the essentiality test is a good help in deciding whether all the features of a dependent claim have to be taken over in the combined claim or not.

    Whether the test is called “essentiality test” or not, or even another name is given to it, is in my opinion not relevant. One has just to look what the person skilled in the art derives directly and unambiguously from the original disclosure. And here we are back to the gold standard of G 2/10…..

    We should not fight for or against a label, but look at what is said in the original disclosure.

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