New EPO Enlarged Board of Appeal decision on priority

Header image:

The Enlarged Board of Appeal of the European Patent Office (EPO) has now issued its full written decision, G 1/15, concerning multiple priorities, toxic priority applications and poisonous divisional applications. The decision makes it absolutely clear that partial priorities shall be recognized, and that no special conditions or limitations shall apply.

The background of this decision is a series of earlier Board of Appeal decisions in which a European patent application or patent was ruled to lack novelty over its own priority document (“toxic priority”), its own divisional application (“poisonous divisional”) or its own parent application. These highly controversial decisions stem from the EPO’s rather strict view of whether a priority application and a later application are related to “the same invention”, as well as a particular interpretation of an earlier Enlarged Board of Appeal decision, G 2/98.

A short example illustrates the problem: A priority application discloses only the metal “copper”, while the later EP application claims “metal” in general. According to the “toxic priority” decisions, once the priority application and the EP application are published, the disclosure of “copper” in the priority application can destroy the novelty of a claim with the broader generic term “metal” in the EP application. This applies if the EP claim is not entitled to a “partial priority” for the part of the claim relating to “copper”. Similarly, the “poisonous divisional” decisions have ruled that subsequent publication of a divisional application that discloses “copper” can destroy the novelty of “metal” in the parent EP application.

According to G 1/15, however, the claim should be split up into two parts, each with its own priority, i.e. “copper” and “metals other than copper”. In this case, the part of the EP claim covering copper is entitled to priority, even though “copper” may not be explicitly mentioned in the EP claim directed to “metal”. This means that the published priority application is not novelty-destroying for the EP claim, since “copper” enjoys priority, and “copper” (disclosed in the priority application) and “metals other than copper” (the remaining part the EP claim) are not overlapping.

This decision from the Enlarged Board of Appeal provides a welcome end to several years of uncertainty on this topic.

Read also: UPC may begin operations in December 2017

Read also: A few questions and answers about Unitary Patents and the Unified Patent Court