In case G1/15 the Enlarged Board of Appeals of the European Patent Office has just released the order of its decision as follows:

"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 full decision should be issued shortly. However, it is already apparent that this decision will clarify the application of partial priority of subject matter contained in a claim in Europe.

The order indicates that when a claim encompasses subject matter disclosed for the first time, directly, or at least implicitly, unambiguously and in an enabling manner in a priority document, partial priority should apply without any other substantive conditions or limitations.

It shall be interesting to analyze the full decision when it is issued in particular, in order to fully understand whether when a claim of a European patent application covers a general subject matter (for example through a generic term), and only a part of this subject matter (an alternative of the more general subject matter) has proper support in the priority document, then this particular alternative may benefit from partial priority.

The decision will probably have an impact on how the scheme of so-called `poisonous divisional applications' should be applied.

This scheme has recently developed in Europe. It can occur in situations where:

  • A priority application was filed, in any jurisdiction recognized by the EPO (Paris Convention state, WTO member state, or a EP or PCT patent application),
  • A European patent application was filed (under direct priority, or as a national phase of a PCT patent application), with claims broadening e.g. through a generalization the content of the priority application,
  • A European divisional application was later filed from the European patent application.

These situations are not uncommon, and a large number of cases are potentially concerned.

In such situations, use of the `poisonous divisional applications' scheme can have a dramatic consequence: the loss of the European patent application, or loss of the European patent if it was already granted.

This is due to the convergence of three aspects of European patent law:

  • A strict approach of priority (in line with the standard established by the landmark decision G2/98),
  • The application of partial priority to the content of the European divisional patent application, with the consequence that new European prior art, relevant for novelty only, is effectively generated for the content of the divisional application that was already present in the priority,
  • Under the poisonous scheme, such new European prior art would be considered as novelty-destroying for the claim with a broadened (e.g. generalized) scope.

This scheme may appear counter-intuitive as the divisional application kills its parent application. However it can be seen as an extension of a 'basic' poisonous priority scheme, where the first European patent application becomes prior art against the claim of a later European patent application filed under priority of the first European application. In such a 'basic' scheme the first application would be prior art (for novelty only) against any claim of the later application that would not enjoy the priority of the first application.

Such schemes have been applied in decisions at the EPO, and were on the way to becoming a standard attack against European patents having a broadened claim. It has also been used before some national courts in Europe in nullity actions.

This scheme has created significant concern and discussions. In view of this, and of some diverging case law, five questions have been referred to the Enlarged Board of Appeals of the EPO (case G1/15, based on T 557/13). Questions 2 to 5 needed to be answered only if answer to question 1 was `Yes'. Therefore this first question is critical in this matter. This question reads:

"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?"

In practice, this question asks whether partial priority should be assessed with a strict, `literal' approach, or with a more generous, `conceptual' approach. The answer to this question would then determine whether European practitioners should continue to live with the `poisonous' schemes.

Third parties were given the opportunity to file written statements in accordance with Article 10 of the Rules of Procedure of the Enlarged Board of Appeal. Many such statements have been filed, the majority of them (including the statement filed by FICPI) advocated in substance to consider partial priority via the `conceptual' approach.

The publication of this order from the Enlarged Board of Appeals brings an end to this matter, as the answer to question 1 is 'No' (and questions 2 to 5 therefore become irrelevant). This confirmation that partial priority is to be appreciated with a `conceptual', generous approach, will probably limit the development of poisonous schemes in Europe. The forthcoming publication of the full decision should provide a complete understanding of the reasoning of the Enlarged Board of Appeals