Two new referrals to the EPO’s Enlarged Board of Appeal on entitlement to priority

Legal context for the referrals

Entitlement to priority may seem a relatively straightforward concept – it belongs to the person who files a patent application, or their successor in title, and can be exercised when filing a later application within the priority year. What could be so complicated about that?

However, because attacking the priority right can be such a potent weapon in opposition or litigation (where there has been a relevant publication in the priority year) there is an extensive and sometimes contradictory EPO and national jurisprudence concerning the priority entitlement requirement.

What most of these cases have in common is that the later application was filed by a different entity to the earlier one, and there was no evidence that an effective assignment of the priority right was made before the later filing^[1]. A typical scenario is one or more inventors being named as applicants on the earlier filing, and some corporate entity being named as applicant on the later one (although there are many other scenarios where the issue has arisen).

In such cases the later applicant may argue that they are nevertheless the successor in title, by virtue of some other agreement or understanding between the parties (for example employment contract, or research agreement, or other arrangement intended to transfer intellectual property). It has even been accepted on occasion that an equitable title in the priority right is sufficient for the later applicant^[2]. Typically the transfer is argued before the EPO by providing evidence relating to the effect of relevant national law^[3].

An alternative argument, which has been accepted in some EPO opposition division cases^[4], but not in others, is based on the so-called “joint-applicants approach”.

The basic “joint-applicants approach” is well established in the case-law, and holds that merely adding one or more co-applicants to a later filing does not negate the priority right, as long as the entitled-applicant is also named as a co-applicant.

The development of that argument, which is relevant here, is the so-called “PCT joint-applicants approach”. This concerns the quite specific scenario in which a US priority filing names one or more inventors as applicants, and those inventors are then later named as applicants only for the US designation on the PCT case, whereas a corporate applicant is named for the EP and other designations. It has been argued in a number of EP cases that the priority claim is valid here because the applicant of the priority application is amongst the PCT co-applicants. Because the PCT applicants overall have the right to priority, it is argued that the EP designation and later EP application also do so, since the priority right in the PCT application has a unitary character for all designated states. This version of the argument essentially by-passes any requirement to show the corporate applicant is an appropriate successor in title to the inventors: rather they can be treated simply as an added co-applicant on the PCT application.

One further argument which has been made before the EPO when trying to defend a challenge to entitlement of the priority right is that the EPO should not concern themselves at all with the determination of that question^[5]. This position would be analogous to the fact that the EPO does not have the power to determine entitlement to grant of a European patent application, which is dealt with by courts of the contracting states^[6]. However it would be contrary to long standing case-law before the Boards of Appeal.

The referrals

The referral of questions to the Enlarged Board was made from two related cases: T1513/17 and T2719/19 (concerning parent and second-generation divisional applications respectively). Both the applications derived from a PCT application claiming priority from a US provisional application filed by three inventors. The PCT application named the three inventors as applicants for the US only, but a corporate entity as applicant for other states including the EPO. On the evidence, only one of the inventors appeared to have assigned their priority rights to the corporate applicant before the PCT was filed. An attempt to “correct” the applicants on the EP application to deal with the problem was not accepted.

The questions referred directly concern two of the three arguments discussed above: namely “EPO jurisdiction” argument, and the applicability of the “PCT joint applicants approach”.

The questions referred are:

1. 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?
   
   
2. 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.

Where to now?

It may be many months before the cases are heard. There is already evidence that pending cases are being stayed where their outcomes depend on the answers to the questions, or at least on Question II.^[7]

While it is too early to predict how the Enlarged Board may ultimately decide this, a few comments can be made.

It seems quite clear from the referring decisions that Question I has been included in the referral primarily because it is a good opportunity to settle the issue of jurisdiction:

“The board is also receptive to the argument of the parties that, if questions regarding priority are to be referred to the EBA on a related matter, this is a convenient opportunity to have a final decision on the "jurisdiction issue" as well.”

As has been noted before, there is a long-standing position in the case-law that the EPO does have jurisdiction to decide this issue, and the arguments to the contrary have not had much traction. Although the Enlarged Board has on occasion reversed well established practice (sometimes with transitional provisions, or on a non-retrospective basis) it would be very surprising indeed if they answered Question I in the negative.

Regarding Question II the issue is likely to be more finely balanced. The referring Board of Appeal considered three possible different legal bases for the PCT joint applicants approach.

The first drew an analogy between the PCT application and a specific provision in the EPC concerning EP applications where there applicants are different for different EPC contracting states, and are nevertheless treated as joint applicants in proceedings before the EPO.

The second was the argument discussed above based on the “unitary” character of the priority right in the PCT.

The Board did not see merit in either of these.

A third argument called into question the practice that the transfer of the priority right is a matter of national law, considering instead that the transfer should be a matter for the EPC legal system. If that were correct, in the absence of formal requirements in the EPC for such a transfer, it could perhaps be sufficient that it was implicit in the naming of the inventors as applicants for the US, that the applicants for all other states should also benefit from the priority i.e. that the PCT application was evidence that the applicant for the EP was the successor title by implicit agreement. In fact the same finding could be made if the governing law was national law, provided the relevant national law permitted implicit transfer.

While all these arguments may seem rather tortuous, they should be seen in context: it is a feature of cases concerning priority entitlement that the consequence of deciding that the applicant lacks entitlement to claim priority (and hence that their patent may be invalid over intervening prior art) can seem entirely disproportionate to any failing by the applicant: it may arise simply from the timing of an assignment from an inventor to other entity, or a carelessness in naming or omitting an applicant, despite the fact that in many instances all these involved parties were working together and intended that the priority claim be effective.

In such circumstances it is easy to see how it could be questioned what public interest there is in striking down patents on this ground^[8]. In that context it would not be surprising if the Enlarged Board did seek to support PCT applicants approach, whether on the basis of the arguments considered by the referring Board, or some new one of their own devising!

References

1. The issues also arise if the same applicant files both applications, but there is a potential transfer of the priority right to a third party in between
2. See e.g. [2016] EWCA Civ 1089 – Idenix v Gilead
3. See e.g. T725/14
4. See Decision of the opposition division dated 4 October 2018 in EP application 06839697.7 here
5. T844/18
6. Protocol on Jurisdiction and the Recognition of Decisions in respect of the Right to the Grant of a European Patent – (Protocol on Recognition)
7. See Minutes dated 7 February 2022 in T419/16
8. See e.g. [2017] EWHC 2711 - Accord v Research Corporation Technologies