Added Matter (2) - The inescapable trap

The EPC contains two principle rules regarding added matter. Firstly, an application or patent cannot contain any subject matter that was not present in the application when originally filed. Secondly, the claims cannot be amended after grant such that the scope of protection is expanded. 

The interaction of these two rules during opposition or litigation after grant can lead to the inescapable trap.  Let's assume an application was filed describing and claiming a bicycle frame made of metal tubes.  During prosecution the claim was amended to claim a bicycle frame made of steel tubes and a patent was granted.  After grant the patent is opposed and the Opponent manages to convince the EPO that there is no basis for steel tubes in the application as filed, but only metal tubes.   

The Patentee is now stuck - the claim as granted is invalid due to the presence of "steel", but this cannot be amended back to "metal", or be removed, as that would broaden the claim compared to how it was granted. The situation is thus "inescapable" because the granted claim is no longer valid and cannot be fixed.  The only hope is to find an amendment that further narrows the claim and is disclosed in the application as filed. 

The test for expanding the scope of a claim is considered very strictly at the EPO and individually in relation to each aspect of the claim. That is, the removal of steel in our example cannot be compensated by introducing other very narrow features, even if the overall claim could be argued to be narrower. The test can be summarised as whether an article would infringe the new claim, but did not infringe the claim as granted. 

The potential consequences of a bad amendment which narrows the scope of a claim are therefore greater than an added matter objection from the Examiner and can lead to loss of the Patent.  Sneaking an amendment past an Examiner can feel like an achievement, but this could be at the risk of loss of the Patent later on. Of course, situations often demand amendments "on the edge", which is fine as long as they are made in full knowledge of the possible outcomes. 

Particularly troubling is that some Boards of Appeal are far stricter on added matter than examining and opposition divisions so it may be only at the very end of procedural options that a claim fails. 

Next week we'll look at how the general added matter rules apply to the ability to combine features from different embodiments. 

This article is a part of our EPO Practice and Peculiarities series. Click here to explore.