Contact Us

A resolution to self-collision?

Katherine Wright, European patent attorney, considers the recent decision by the Enlarged Board of Appeal regarding partial priority, and whether this could remove the risk of self-collision. 

Over the past few years, the issue of partial priority and the associated risk of self-collision has become a real problem faced by European patent applicants and attorneys. This issue may arise when, for example, a patent application is filed with claims that are broader than the disclosure of an earlier application from which it claims priority. If the earlier application proceeds to publication, then unless the later application is entitled to priority in relation to the parts of the claim present in the earlier application, the earlier application will be prior art against the later one and could lead to a finding of lack of novelty. Similar issues can arise where a divisional application is filed (a so-called “poisonous divisional”), the act of filing a divisional application in effect creating prior art that would not otherwise exist.

There has been much discussion of the anomalous and indeed – in most people’s estimation – absurd consequences of this issue. The matter was referred to the Enlarged Board of Appeal of the European Patent Office in 2015 (see IP News article ‘Can patent claims have partial priorities?) as Case G1/15, and the Enlarged Board’s reasoned decision in G1/15 has now been published.

The previous position, which resulted from Enlarged Board of Appeal decision G2/98, was that a claim could have multiple priority dates only if it gave rise to a limited number of clearly defined alternative subject matters.

However, the Enlarged Board of Appeal has now stated that “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 Enlarged Board states that priority is a right provided by both the Paris Convention and the EPC, and the only substantive condition for being entitled to priority is that the application is directed to the “same invention” as that from which it claims priority.

The Paris Convention and EPC further allow for a single claim to claim multiple priorities, and partial priority (in which only a part of the claim is entitled to priority) is a sub-set of this. The Enlarged Board held that, in the case of partial priority, the elements which can be directly and unambiguously derived from the priority application as a whole constitute what may benefit from partial priority. 

Commenting on G2/98, the Board states that, where a right is provided for by an international treaty, convention or national law, it cannot be limited by applying additional conditions from administrative rules or guidance, or jurisprudence. Hence, G2/98 cannot be construed as further limiting the right of priority.

In practice, if subject-matter derivable from the priority document is encompassed by the claim of the application/patent claiming priority, then that subject matter will be entitled to priority. Any remaining subject matter is not entitled to priority, but may form the basis for a priority claim of a later application.

This decision appears to remove the risk of self-collision, by removing the additional requirement imposed by G2/98 that partial priority could only be recognised if there were a number of clearly defined alternatives. Any subject-matter derivable from the priority document which is encompassed by the priority-claiming application will be entitled to its priority claim. The priority document cannot be used to destroy the novelty of an application claiming priority from it, because any information for which the priority document could be novelty-destroying, ie which is present in both applications, will be entitled to the priority claim.

Need some advice?

Call us on +44 (0) 115 947 7977 to speak to
one of our IP experts based in Nottingham, Leicester and London.

Providing professional services of the highest quality