After four years of the European Patent Office (EPO) ruling that a parent application can lack novelty over its divisional application, and vice versa, the EPO Enlarged Board of Appeal (EBA) in their decision G1/15 has finally put an end to this familicidal practice.

The background of this dilemma was previously reported here, which outlined the fundamental issue of how entitlement to priority is determined. The ‘poisonous’ scenario arose when a parent European application was strictly not considered entitled to priority, for example due to a broader claim than in the European priority application. A narrower disclosure, entitled to priority, appearing in the publication of a European divisional application would then be considered to be novelty destroying. This could of course work both ways, and the publication of a parent application could also be considered to anticipate a divisional application with claims not considered entitled to priority.

A remedy to this scenario was provided in a number of EPO Board of Appeal decisions which, instead of the traditional strict literal approach, employed a more liberal “partial” approach to assessing priority entitlement. This involved conceptually dividing a generic claim, which does not explicitly separate different embodiments, into two parts. The first encompassed the disclosure of the priority application and therefore is entitled to priority. The second covers disclosure(s) additional to the priority application and is therefore not entitled. However, the family member publication for this additional disclosure is also not priority entitled, and so can never be novelty destroying.

Due to conflicting case law, a series of questions were referred in case G1/15 to the EBA. The first question read:

  1. Where a claim of a European patent application or patent encompasses alternative subject-matters by virtue of one or more generic expressions or otherwise (generic “OR”-claim), may entitlement to partial priority be refused under the EPC for that claim in respect of alternative subject-matter disclosed (in an enabling manner) for the first time, directly, or at least implicitly, and unambiguously, in the priority document?

The remaining questions, including directly whether a divisional application is per se able to anticipate its parent, relied on the answer being yes. However, at the end of November 2016 the EBA emphatically answered no, issuing an order (previously covered here) which stated:

Under the EPC, entitlement to partial priority may not be refused for a claim encompassing alternative subject-matter by virtue of one or more generic expressions or otherwise (generic “OR”-claim) provided that said alternative subject-matter has been disclosed for the first time, directly, or at least implicitly, unambiguously and in an enabling manner in the priority document. No other substantive conditions or limitations apply in this respect.

The fully reasoned decision, released at the beginning of February this year, clearly adopted the conceptual partial priority approach to arrive at its conclusion. Notably, the EBA relied heavily on the Paris Convention.

Point 5.2.3 of G1/15 states:

Under Article 4F of the Paris Convention, priority may not be refused on the ground that the applicant claims multiple priorities, or on the ground that an application claiming one or more priorities contains one or more elements that were not included in the application or applications whose priority is claimed, provided that, in both cases, there is unity of invention within the meaning of the law of the country.”

Point 6.1 then goes on to quote Article 4H of the Paris Convention:

“Priority may not be refused on the ground that certain elements of the invention for which priority is claimed do not appear among the claims formulated in the application in the country of origin, provided that the application documents as a whole specifically disclose such elements.”

Most interesting is how they applied this to, and construed, the earlier EBA decision G2/98 on multiple priorities. Point 6.7 of that decision outlines that multiple priorities are allowed “provided that it gives rise to the claiming of a limited number of clearly defined alternatives”. As opposed to overruling this, they made a distinction between multiple priorities and partial priority, regarding the latter as a sub-group of multiple priorities (points 5.3 and 6.3 of G1/15). As a result the proviso in G2/98 “cannot be construed as implying a further limitation of the right of priority”.

Ultimately, the conceptual division is confirmed as the correct approach for assessment of partial priorities. The first step is to determine if the subject matter is directly and unambiguously disclosed in the priority document. The next step is to examine whether this subject matter is encompassed by the claim of the application or patent claiming said priority. If the answer is yes, the claim can be divided into two parts (point 6.4 of G1/15).

Unsurprisingly, the final section confirms that the remaining questions referred to the EBA do not need to be considered.

While it may be too late to bring back patents and applications lost to the short-lived phenomenon of poisonous family members, this decision is clearly very good news for patent owners and applicants who no longer have to fear filing divisional applications in Europe.