The Patentability of Diagnostic Methods at the EPO
In the light of conflicting decisions of the Technical Board of Appeal, the President of the EPO referred a number of questions to the Enlarged Board of Appeal (EBA) so that its stance on the patentability of 'diagnostic methods' could be clarified. The EBA has ruled on these questions in G1/04.
Of those conflicting decisions, the two which most clearly highlight the difference in how Article 52(4) EPC (which excludes diagnostic methods practiced on the human or animal body from patentability) should be construed are T 385/86 and T964/99.
In T 385/86, a narrow construction was adopted and only methods whose results immediately made it possible to decide on a particular course of medical treatment were excluded. Thus, methods not containing all the steps involved in making a diagnosis were not excluded.
In T 964/99, a far broader construction was adopted and it was held that as the purpose of Article 52(4) EPC was to exclude all diagnostic methods practiced on the human or animal body, or which were of value for the purpose of diagnosis, a method comprising one step which served a diagnostic purpose or related to diagnosis should be excluded from patentability.
So what is a 'diagnostic method' for the purposes of Article 52(4) EPC?
In assessing how Article 52(4) EPC should be construed, the EBA took the view that the steps which must be taken in order for a diagnosis to be made are:
i) an examination phase involving the collection of data,
ii) a comparison of these data with standard values,
iii) a finding of any significant deviation during the comparison, and
iv) the attribution of the deviation to a particular clinical picture, i.e. the deductive medical or veterinary decision phase.
The EBA considered whether for diagnostic methods to be excluded from patentability by Article 52(4) EPC they need only comprise step iv), or whether they must additionally comprise one or more of preceding steps i) to iii).
As step iv) is an intellectual exercise, i.e. a mental act, that step alone is not considered to be an invention under the provisions of Article 52(2)(c) EPC. Thus, to comprise an invention that is excluded from patentability under Article 52(4) EPC, step iv) must be preceded by steps of a technical nature.
The EBA found that this reasoning was compatible with the language of Article 52(4) EPC, which excludes "diagnostic methods practised on the human or animal body" from patentability. The provision does not make reference to particular steps of such methods, nor does it contain wording such as "relating to diagnosis" or "of value to diagnostic purposes". Thus, the exclusion should be construed narrowly, such that the method must be complete and include all steps relating to it.
Importance of the participation of a medical practitioner
A further point that was considered was whether the identity of the person who would practice the method was relevant to the Article 52(4) EPC exclusion.
It was held by the EBA that for the purposes of assessing whether a diagnostic method was excluded from patentability by Article 52(4) EPC, it is irrelevant who, in practice, will perform the method.
The extent to which a diagnostic method must be practiced on the human or animal body
According to the EBA, a diagnostic method will only be excluded from patentability if all the method steps (e.g. steps i to iii above) are "practiced on the human or animal body".
Article 52(4) EPC does not require a specific type of interaction with the human or animal body - a step in a diagnostic method satisfies the criterion "practiced on the human or animal body" if its performance implies any interaction with the human or animal body, necessitating the presence of the latter. This includes invasive and non-invasive interactions.
The EBA specifically ruled that if some or all of the method steps are carried out without implying any interaction with the human or animal body, for instance by using a specific software program, or in vitro, these can not said to be "practiced on the human or animal body".