Oral proceedings in cases G 1/22 and G 2/22 ("Entitlement to priority")

Oral proceedings in cases G 1/22 and G 2/22 (

Share on social media

25 May 2023

The oral proceedings in cases G 1/22 and G 2/22 ("Entitlement to priority") before the EPO Enlarged Board of Appeal will be held on 26 May 2023. The public and members of the media will be able to follow the proceedings online via live stream on zoom via the link as here.


In February of last year, EPO Board of Appeal 3.3.04, by interlocutory decisions T 1513/17 and T 2719/19 (consolidated proceedings), referred two questions to the Enlarged Board of Appeal under G1/22 and G2/22.  These questions concerned the assessment of the EPO regarding entitlement to priority. On 21 March 2023, The Enlarged Board of Appeal issued its preliminary opinion in respect of these two important questions concerning whether the European Patent Office can decide on entitlement to a priority right, and if the “joint applicants approach” is to be applied to PCT applications where different applicants are listed for different states.  While the analysis of a substantive right to priority considers whether the invention can be derived from the priority document, the analysis of formal priority entitlement to priority determines whether the party claiming priority from the earlier application has the right to do so, if the later application is filed in a different name. In both technical board of appeal cases at the origin of this referral, a PCT application claimed priority from a US provisional application filed in the name of multiple inventors which were designated in the PCT application as applicants for the US only. For other states, including the EPO, the applicants identified in the PCT filing were corporate entities. The formal entitlement to priority which was not questioned during the EPO granting procedure, is being questioned by third parties during opposition procedure against the granted patents.

Below we give some insight into to points dealt with in the preliminary opinion of the Enlarged Board of Appeal which will be central to the upcoming oral proceedings of 26 May 2023.

The outcome of these cases could have a significant impact on how priority will be assessed before the EPO.

The Referred Questions

The  two questions read as follows:

I. Does the EPC confer jurisdiction on the EPO to determine whether a party validly claims to be a successor in title as referred to in Article 87(1)(b) EPC?

II. If question I is answered in the affirmative

Can a party B validly rely on the priority right claimed in a PCT-application for the purpose of claiming priority rights under Article 87(1) EPC

in the case where

1) a PCT-application designates party A as applicant for the US only and party B as applicant for other designated States, including regional European patent protection and

2) the PCT-application claims priority from an earlier patent application that designates party A as the applicant and

3) the priority claimed in the PCT-application is in compliance with Article 4 of the Paris Convention?

These questions are pending under referrals G1/22 and G2/22 and will be treated in consolidated proceedings.

The first and very broad question concerns the competence of the EPO to assess whether a party is the legitimate successor in title of the applicant for the first, i.e. the priority application. This issue has previously been raised in several Board of Appeal Decisions.

The second question focusses more deeply on the specific facts of multiple parties named on the PCT application for different states and whether the “joint applicant approach” which is applied for direct European applications also applies to PCT application. For instance, whether a corporate entity not named as applicant in the first application but named as applicant for the PCT application is entitled to claim priority to this first application, when the inventors are co-applicants for another country. This is a situation most commonly occurring for PCT applications claiming priority from US provisional applications filed before March 2013 (pre-AIA), as since then US inventors are no longer considered applicants on US applications. However, the question remains relevant as many of these cases are still under patent dispute.

In abeyance of the outcome of the EBA referrals, the EPO has issued a Notice informing that all examination and opposition proceedings before the EPO  in which the decision depends entirely on the outcome of the referrals will be stayed until the EBA has issued its decisionThis concerns all cases where Art. 87(1) EPC is relevant, so all cases where there is intervening prior art in case the priority would be found not to be valid. This is often the case for research organizations that publish their results shortly after filing. The issue only arises however if there is no evidence that the priority right was transferred from the named applicant of the priority application to the named applicant of the PCT application before the filing date thereof.

As part of the procedure before the Enlarged Board of Appeal, third parties were given the opportunity to file written statements to the EPO detailing their position on these issues. Different entities as well as patent attorney firms (many of which were involved in oppositions where this issue was raised) and some intellectual property organizations filed such “amicus curiae briefs” as can be found here.

Do we know more?

The Communication issued by the Enlarged Board of Appeal on 21 March 2023 indicates the points and legal considerations they consider to be of most importance for discussion at the proceedings.  The communication also sets out some preliminary views of the Enlarged Board of Appeal regarding the referred questions I and II.

Firstly, the communication confirms that the Enlarged Board of Appeal considers the referral to be admissible, and unless indications to the contrary will not address this matter again.

Regarding Question I, the Enlarged Board of Appeal in it’s communication does not make any conclusion or decision but draws attention to the principles underlying Article 87 EPC, including its relation to Article 60(3) EPC, according to which, the applicant shall be deemed entitled to exercise the right to a European patent in proceedings before the EPO.

In particular, the Enlarged Board of Appeal points to the following five questions which it intends to consider with regard to answering question I:

Has the case law always been (implicitly or explicitly) supporting the EPO’s competence to assess entitlement to priority? It should be noted that in reality objections based on the entitlement to priority became routine in opposition proceedings only from about 2010.

Does Article 60(3) EPC have no impact on the interpretation of Article 87 (implying answering question I with ‘yes’) or should the latter be understood in light of the former (implying answering question I with ‘no’)?

Should formal entitlement to priority be assessed ex officio in examination proceedings?

Could an assessment of entitlement to priority be made on the basis of the autonomous law of the EPC (i.e., without invoking national law)?

If the EPO has the competence to assess entitlement to priority rights, is it also competent to assess the entitlement to the priority application of the respective applicant?

The Enlarged Board of Appeal has thus a structure for the discussion of question I during the oral proceedings on 26 May 2023.

Furthermore, for question I, the communication confirms that the Enlarged Board of Appeal considers that the question encompasses all situations where the applicant claiming priority is not clearly identical with the applicant of the priority application, and that the question refers not only to priority filings in or for members of the WTO (Art. 87 (1)(b) EPC) but also to priority filings in or for States party to the Paris Convention (Art. 87(1)(a) EPC).  The communication also provides clarification as to the interpretation of particular terms used in the question.  The Enlarged Board of Appeal notes that the term ‘jurisdiction’ should not be misunderstood in a way that, in case question I was answered in the negative, the EPO would not be in a position to proceed in a pending case after entitlement to priority becomes an issue.

For question II, the communication provides a more defined point of view.  The Enlarged Board of Appeal leans towards a positive answer, assuming the first question is also answered in the affirmative.  In arriving at this preliminary view, the communication outlines how, at this time, the Enlarged Board of Appeal has reservations regarding the ‘PCT joint applicants approach’ that implies that in a PCT application where parties A and B are applicants for different designated states, both applicants may rely on the priority right derived from a priority application filed by only one of the applicants.  Instead, the Enlarged Board of Appeal is of the preliminary view that all applicants of a PCT application may enjoy a priority right acquired by only one of the applicants if a formal or informal agreement exists or is assumed to exist between the applicants on the sharing or transfer of the priority right.   The Enlarged Board of Appeals notes that the fact that a PCT application was jointly filed (i.e., with the consent of all applications) could serve as evidence for the existence of such an informal or implied agreement.

The Parties in the referring cases had until 5 May 2023 to make any further submissions in advance of the Oral Proceedings. All documents can be found here and here.

It appears from this communication that question 1 is going to be the most debated part of the Oral Proceedings. The impact of this will be considerable, given that the validity of a number of applications depends on it. If it is decided in the affirmative however, it is likely that further decisions will be necessary to clarify what is a valid priority claim. The Enlarged Board of Appeal is not bound in any way by this communication. It  will be interesting to see whether they give any further insights into where there answers are going  this Friday on 26 May 2023.  We look forward to providing further updates as the case develops.

If you have any questions, we would be happy to help. Feel free to reach out to our European Patent Attorneys via email on

Follow us on Instagram