Added Matter (8) – Roundup

Over the previous seven articles we have discussed a range of key topics relating to the EPO's added matter rules. In this last article in the set, we round up some key points on this topic. 

Content of the Application 

As we have discussed, amendments must find basis in the application as filed, but it is important to remember that this does not mean everything filed as part of the application.  In particular, for the purposes of the added matter rules, the abstract is not considered part of the application and so cannot provide basis for amendments.  Priority documents also do not form part of the application as filed. 

Although the background section is part of the application as filed, it is usually very difficult to use it for basis because the disclosure is expressly not in relation to the invention. Care should be taken to ensure any general introductory material which may be relevant is expressly disclosed in relation to the invention. For example, the technical area should be defined both in the detailed description as well as the background. 

For applications originating in the USA, the use of incorporation by reference is relatively common. However, the referenced documents are not recognised as part of the application as filed and so cannot provide basis for amendments. There is a very narrow exception which allows referenced documents to be used to provide sufficient disclosure, but this does not apply for basis for amendments. 

Where a European application is derived from a PCT application, the disclosure of the PCT application as filed is the disclosure against which basis is assessed. The only exception to this is where claims have been abandoned due to non-payment of excess claims fees.  Any claims abandoned in this way are lost and are considered not to have been part of the application as filed (but the same subject matter in the description would be retained). 

Lists 

The use of lists as basis for amendments is a special area which occupies tomes of case law.  The rules are extremely fact-specific, but there are some general principles that are useful to understand.  Selections from one list ("Part x may be a, b, or c") are generally permitted.  However, selections from two lists ("Part x may a, b, or c, and part y may be d, e, or f") are generally not permitted because each element of one list is not disclosed in direct and unambiguous combination with each element of the other list. 

There are numerous special cases and exceptions but following this general principle and not relying on combining lists is the safe approach. 

Deletion of Features 

Deleting features from an embodiment have previously been considered as a special case for assessing basis to which a particular set of tests apply.  However, recently case law has moved away from these tests and assessed deletions on the same principles as other amendments -- if there is direct and unambiguous basis for the remaining features.  

The previous tests can still be helpful as guidance for the assessment, but they are not definitive. For reference the tests are (1) is the feature explained as essential, (2) would the skilled person directly and unambiguously recognise that the feature is not indispensable for the function of the invention, and (3) is further modification of other features required to compensate for the deletion. 

Numerical Values 

Due to the strict nature of the added matter rules, even seemingly innocuous changes like changing the accuracy or rounding numerical values can lead to added matter problems.  The scope of a point value of 10 would extend from 9.5 to 10.4, but if the value is amended to 10.0 it would only cover 9.95 to 10.04 thereby changing the scope to something for which there may not be basis.  More concerning is that if this was challenged in opposition the claim may become stuck in the inescapable trap (Article 2 in this series) as reverting the value would broaden the claim. Care therefore needs to be taken with any changes to how numerical values are expressed. 

The EPO's added matter rules are some of the more challenging aspects to successful patent prosecution in Europe.  Hopefully this set of articles has been helpful in understanding the general principles and how some common problems can be avoided.  There are, of course, extensive nuances, traps, and opportunities which can only be avoided or utilised with specific assistance, starting at the outset of a case, from a knowledgeable and skilled European attorney who works with these issues every day. 

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