EPO priority claim entitlement – the “same applicants” approach upheld


In a Press Communiqué dated 6 November 2020, the EPO summarises the Technical Board of Appeal 3.3.08 written decision recently issued in case T 844/18 confirming the revocation of a patent related to CRISPR gene editing. The revocation was based on a lack of novelty due to an invalid claim to priority. The Communiqué from the EPO summarises the Board’s findings as follows:

The first question addressed by the Board was whether entitlement to priority should be assessed by the EPO or rather in entitlement actions before national courts. The Board concluded that Article 87(1) EPC both empowered and obliged the EPO to assess the validity of a claim to priority.

The second question was how to interpret the expression "any person" in Article 87(1) EPC. Under the established practice both at EPO and national level, a valid priority claim requires that all persons listed as applicants for the priority application are also listed as applicants for the subsequent application, allowance being made for successors in title. The Board confirmed this so-called "all applicants" approach.

A third question concerned whether national law (in this case US law) governs the determination of "any person" who has "duly filed" under Article 87(1) EPC. On this point, the Board concluded that the Paris Convention was the law which determines who "any person" is.

For these reasons, the Board found that priority had not been validly claimed from several US provisional applications. Therefore, documents became relevant prior art over which the claimed subject-matter was not novel. The Board thus dismissed the patent proprietors' appeal against the opposition division's decision to revoke the patent.

In our previous article on priority entitlement at the EPO (found here), we explained that it is existing EPO practice that an earlier application can only serve as a basis for claiming priority for the filing of a subsequent application if the subsequent application names all applicants of the earlier application or their successor(s) in title (the so-called “same applicants” or “all applicants” approach).

This practice was confirmed in the EPO Appeal decision number T 844/18, relating to The Broad Institute’s CRISPR European patent (EP2771468), claiming priority from a number of earlier US provisional applications. Thus, our earlier best practice points remain unchanged:

  • the subsequent application should name all applicants of the earlier application or their successor(s) in title;
  • the subsequent application should name the above as applicants for the EP designation if the subsequent application is a PCT application;
  • the addition of applicants to a subsequent application is not precluded.

Our other best practice points in relation to assignments can be found in our earlier article.

Now that the full reasoning that led to the decision of the Board of Appeal has been published, our consideration of the written decision is provided below. Overall, the Board made it clear that the formal requirements of the EPC are as important as the substantive requirements of the EPC and as such a patent or a patent application can be lost for formal reasons. Of note, the Board explicitly stated that “applicants wishing to use US provisional applications should be aware of the difficulties they may face if they use these applications to claim priority for a European patent application”. That is, applicants should be aware of the EPC formal requirements at the time of filing their priority and subsequent (priority-claiming) applications to ensure that they fulfil the EPC requirements, should they wish to obtain a European patent.

Background of the case:

The Broad CRISPR European Patent 2 771 468 was opposed by nine parties (reduced to 7 at Appeal). During opposition proceedings, the opposition division found that priority had not been validly claimed from four out of the twelve US provisional applications. As a consequence, the Patent was found not to be novel over the disclosure of two prior art documents.

Questions addressed by the Board:

During the Appeal proceedings, the Appellants set out their arguments in the form of three questions:

The Oral proceedings were held in January 2020 during which the Board of Appeal followed current EPO practice and upheld the decision of the Opposition Division.

The Board also stated that a referral to the Enlarged Board of Appeal was not necessary, because the EPO have adopted a consistent interpretation of Article 87(1) EPC since the inception of the European patent system and the questions raised could be answered beyond doubt by the Board itself.

A summary of arguments raised during the proceedings is provided below.

The Appellants argued that a substantive legal assessment of the right to a priority claim should not be carried out by the EPO. In particular, the Appellants argued that entitlement to priority is a property right which should be assessed by national courts, as for any other property rights. The Appellants referred to Article 60(3) EPC and the Enlarged Board of Appeal decision G 3/92 according to which the EPO does not adjudicate on the ownership of a patent, but rather leaves it to national tribunals. However, the Board found that “whilst the wording of Article 60(3) EPC states that an 'applicant shall be deemed to be entitled to exercise the right to a European patent', there is no corresponding provision in the EPC referring to exercising a right of priority. The absence of a provision in the EPC does not mean that there is a gap in the law that necessarily requires to be filled by analogy from another provision of the EPC.”

The Appellants also argued that there is already a connection between the applicants of the priority application and the applicants claiming priority in a subsequent application, because the priority application is not publicly available before filing the subsequent application. The Appellants argued that the “same invention” requirement was sufficient to maintain certainty for third parties. Whilst the Board agreed that there would be “a 'connection' between the applicants for the priority application and the subsequent application because of the non-public nature during a certain period of time of the priority application”, the Board stated that “deficiencies in formal requirements may result in the loss of the priority right (Article 90(5) EPC). The failure to comply with a formal requirement of the EPC can destroy a patent or patent application, irrespective of whether it satisfies the substantive requirements for patentability.”

The Board concluded that the instances of the EPO are empowered and obliged to assess the validity of a priority right as required by Article 87(1) EPC.

It was acknowledged by all parties that the current and accepted EPO practice requires identity between the applicants of a priority application and the applicants of the subsequent application. This practice is referred to as the “same applicant” or “all applicants” approach.

The Appellants argued for a change of practice of the EPO to one where, "'any person' in Article 4 Paris Convention (and Article 87 EPC) must be interpreted to mean that any one who duly filed the priority application (or his/her successor in title) can validly claim priority. That is, if there are multiple applicants for the priority application, one, a plurality of these applicants, or all of them, can validly claim priority.” In this regard, the Board stated that the EPC is a special agreement within the meaning of Article 19 Paris Convention and thus “any person” is to be interpreted in accordance with Article 4A Paris Convention.

The Appellants argued, inter alia, “that the ordinary meaning of 'any' in 'any person' is not 'all'. If one regards the EPC, the words 'jedermann', 'celui qui' and 'any person' are open and permissive terms and equally open, permissive language is used in the Paris Convention. This was acknowledged by the opposition division for the English and German versions of the Paris Convention, but not for the French.” The Board said that “the term "celui qui" in the authentic French text of Article 4A of the Paris Convention is perhaps less ambiguous and more likely to support the 'all applicants' approach.” Ultimately, the Board came to the view that the ordinary meaning of “any person” in all the language versions is ambiguous, and that the Board “must turn to the object and purpose of the Paris Convention, and more broadly, public policy considerations, in order to interpret 'any person'.” In the Board's view, “the object and purpose of the Paris Convention cannot form the basis for favouring one or some persons to the detriment of all other persons who originally formed part of the group of persons that filed a patent application.” The Board added that “if a group of persons decides together to carry out this act of filing, then they have decided to act as a unity for this purpose, thus implying that the 'any person' is this group as such. As argued by the respondents, it is this action which the Paris Convention seeks to facilitate, namely, using the legal concept of priority, applicants can be treated as if they had simultaneously filed the same patent application in a multiplicity of member states of the Paris Union.”

The Appellant referred to the recent cases of Accord Healthcare -v- Research Corporation Technologies [2017] EWHC 2711 (Ch), from the UK, and Riendeau -v- Zehnder Group International AG, of the Swiss Federal Patent Court, 21 March 2018, as supporting the view that the "all applicants" approach applied by the EPO is incorrect. The Appellant also used these cases to support the “argument that a consequence of the 'all applicants' approach is to use disputes over ownership of a property right to destroy the property right itself, such an outcome being contrary to the object and purpose of the Paris Convention.” The Board dismissed these arguments based on the facts that the UK case (Accord Healthcare -v- Research Corporation Technologies) relates to a question of successorship of title rather than the question at issue, and the Swiss case (Riendeau -v- Zehnder Group International AG) actually applied the established EPO approach in its decision, the passage being referred to by the Appellants appearing to be an obiter dictum regarding the actual decision.

The Appellants also argued that the EPO case law referring to the “all applicants” approach was concerned with “'internal' priority claims: that is both the priority and subsequent applications were European applications.” The Appellant argued that, in contrast, the present case was concerned with “external” (non-European) priority claims, “whereby priority rights are determined by the provisions of the Paris Convention alone” and the EPO’s “all applicants” approach does not apply. The Board disagreed and was of the opinion that there was no reason to make a distinction between Article 8(2)(a) PCT and Article 8(2)(b) PCT cases for the purpose of establishing the meaning of "any person". The Board stated that “the EPO is obliged to apply Article 4A of the Paris Convention in the same way regardless of whether it is faced with an 'internal' priority under Article 8(2)(b) PCT or an 'external' priority under Article 8(2)(a) PCT.”

Finally, the Appellants argued that co-ownership of a priority right was being used by the EPO to avoid “the multiplication of proceedings with identical content (which could lead to multiple patenting)”. The Board agreed with the Appellants that “the priority mechanism was not meant to, and in certain circumstances is unable to prevent multiple applications”. The Appellants pointed out that the “all applicants” approach “could lead to the loss of the priority right, and hence possibly of the patent application, in the situation where one of the applicants is holding the others to ransom by refusing to join in as an applicant for the subsequent application”. The Board disagreed and stated that “an applicant can progress a patent application before the EPO without the active participation of the other applicants even though they are named in the application.” The Board also considered that there is “further policy justification for the current practice: it protects applicants from being "left out" and being forced to resort to international litigation in order to protect their rights.”

The Board concluded that the Appellant did not identify a convincing policy reason for overturning the well-established practice of the EPO.

The Appellants argued that the national law of the country where the priority application was filed is the law that should be used to determine, not only the “duly filed” and “successor in title”, but also the meaning of “any person” under Article 87 EPC, as well as Article 4A Paris Convention. The Appellants argued that “in the period between the filing of the priority application and the subsequent application, it should be possible to tell who 'any person' is, and this can only be determined at that moment in time by the national law applicable to the priority application. The relevant system of law cannot be changed later depending on where any subsequent application is filed”. This point was relevant in view of the US approach according to which “an inventor is an applicant, or 'any person', only for the subject-matter of inventions to which they contributed. Unlike under the EPC, a person's applicant status does not depend on being named in the application.” The Appellant argued that “in the present case the Subsequent Application was filed by all those persons who, as a matter of US law, had filed the Priority Application(s) in respect of the invention that was claimed in the Subsequent Application, hence these persons are the 'any person' required under Article 87(1) EPC”.

The Appellants also argued that disregarding the national law of the country where the priority application was filed for the assessment of the meaning of “any person” contravenes the Paris Convention in that “the validity of a claim to priority would depend on the formalities imposed by the country in which the subsequent application is filed.” The Appellants argued that when applying the principle of “national treatment” (i.e. treat foreigners in the same way as its nationals), the EPO should accept “the system of naming applicants in the country where the priority application was filed.” The Board disagreed and stated that the “national treatment” did not mean that applicants and patentees from non-member states should be treated in the same way as they would have been treated in their home country, but rather that applicants and patentees from non-member states should be treated in the same way as applicants and patentees from member states.

The Board explained that “Article 4A(1) and (2) Paris Convention (and the basically identical Article 87(1) and (2) EPC) do not refer to the 'inventor' or the 'applicant' for a patent application: they refer to a person who has carried out an act, that of filing a patent application.” “Whether these persons are the inventors of what is claimed or whether they are actually entitled to be the applicants for this patent are not issues requiring investigation under the Paris Convention.” Referring to the discussions at the Fourth Session on 9 November 1880 of the International Conference for the protection of industrial property, the Board explained that “the Paris Convention, being an integral part of US law, determines who 'any person' is, and that this determination is a purely formal one. It does not require that the 'any person' is actually legally entitled to make the filing, but merely that they did so.” Finally, the Board said that “it is clear that applicants wishing to use US provisional applications should be aware of the difficulties they may face if they use these applications to claim priority for a European patent application. This is simply a consequence of the US's adhesion to the Paris Convention.”

The Board found that the "national law" that determines who "any person" is, is in this case, the Paris Convention, the interpretation of which is set out under the second question above.