As there is no specific European regulation regarding selection inventions, the only guidance on this issue comes from European Patent Office (EPO) decisions and decisions issued by the courts in the context of nullity actions against patents seeking to protect selection inventions.

The doctrine stemming from the decisions of the EPO Appeals Board has been set down in the Guidelines for Examination, specifically in Rule 9.8, Chapter IV, which analyses the requirement for novelty and inventive step for selection inventions. Such inventions deal with the selection of individual elements, subsets or sub-ranges which have not been explicitly mentioned within a larger known set or range. Therefore, selection inventions constitute a selection of something which forms part of the state of the art.

The interpretation of the novelty and inventive step requirements for this type of invention has significant repercussions for the protection of technological advances in certain sectors, particularly those advances achieved in the chemical and pharmaceutical industries. If one chooses to protect a selection of a chemical compound defined broadly in a previous invention, that selection will have its own protection - that is, upon the expiration of the first patent, the owner of the second one will continue to have an exclusive right to the selected element. Therefore, selection inventions are caught between the need to reward technological innovation and the need to prevent an artificial extension of exclusivity rights.

The Guidelines for Examination are not binding on the courts of those countries covered by the European Patent Convention, although they are used to interpret the convention and national laws. This was the case in a judgment issued by Section 15 of the Barcelona Provincial Court on 18th October 2007; the doctrine of this case also appeared in a judgment of 17th March 2008.

This judgment is particularly interesting because it involved an exhaustive analysis of the novelty requirement in the context of selection inventions, and indirectly of the inventive step requirement. Although the fulfilment of the inventive step requirement was not an object of discussion with regard to the invention whose nullity was sought (according to Article 56 of the convention), the delimitation of the novelty requirement allowed the court to specify the issues which go beyond the concept of novelty and pertain to inventive step.

The main points of the judgment, some of which are applicable to all types of patent, are as follows:

  • The requirement of novelty is jeopardised not only by the explicit contents of a previous document, but also by any element which an expert considers to be implicit in the explicit statements.
  • If the lack of novelty is based on the implicit findings of a prior invention, the subsequent solution must be a solution at which an expert on the subject would have inevitably arrived. 'Inevitable' means a 100% probability, so the novelty would be jeopardised only in the event that the subsequent solution was inferred directly and unequivocally from the description. 
  • It is not necessary to evaluate novelty based on what an expert deems obvious in light of a prior invention because such analysis is in fact the analysis of inventive step. Rather, what needs to be evaluated is whether the expert considers obvious that the subsequent solution was already anticipated by the first invention. 
  • The fact that the components that make up the subsequent invention are expressly present to some degree in the previous document does not automatically mean that the invention lacks novelty. In such cases, one must consult the double list principle found in Decision T12/81 of the EPO Boards of Appeals, which has been incorporated into Rule 9.8 of the Guidelines for Examination. 
  • The double list principle is based on the existence of a significant number of options on the prior invention. The higher the number of options and the more complex they are, the less unequivocal and inevitable the conclusions reached by the selection invention will be. According to the aforementioned Rule 9.8, if two or more starting substances are needed to prepare that product and there are citations of individual examples of each type in two or more lists of a considerable length, the resulting substance of the combination of a specific pair taken from these lists confers novelty. The novelty is due to the fact that the combination chosen from a wide variety of existing possibilities has not been made known to the public. 
  • The complexity and length of the variety of options constitutes the crux of the double list principle: the formal existence of two starting lists is not enough. If two lists of substances which offer enough different alternatives are combined, the final product will be one or the other according to the selection made. This substantiates the affirmation that the consequence is not inevitable, unequivocal and 100% certain from its description, but rather a novel modification of the starting substances explicitly described. 
  • As indicated in Decision T396/89 of the EPO Boards of Appeal, it may be easy, given knowledge of a later invention, to select from the general teachings of a prior art document certain conditions and apply them to an example in that document, so as to produce an end result having all the features of the later claim. However, success in so doing does not prove that the result was inevitable. All that it demonstrates is that, given knowledge of the later invention, the earlier teaching is capable of being adapted to give the same result. Such an adaptation cannot be used to attack the novelty of a later patent.

The application of the above guidelines has led the Barcelona Provincial Court to recognize the novelty of the selection invention under analysis. With respect to this same invention, the courts in Austria, the United Kingdom and the Netherlands have applied more restrictive criteria with regard to the double list principle on which the selection inventions rest and ruled for the nullity of the patent.