The European Patent Office (EPO) is known for its strict approach to added matter. The true test for an allowable amendment is whether the claimed combination of the amendment is directly and unambiguously derivable from the application as filed. One exception to this rule can occur when a claim is amended by the addition of a disclaimer.

As defined by the Enlarged Board of Appeal case G 1/16, disclaimers are defined as negative limitations expressly used to restrict subject matter without contravening Article 123(2) EPC. The decision also further defined disclosed and undisclosed disclaimers.

  • Disclosed disclaimers explicitly disclaim a feature which previously formed a possible embodiment of the invention. Such features are transformed from "positive features" to "negative features".
  • Undisclosed disclaimers explicitly disclaim a feature which was not described or disclosed in the application as filed.

As established in the Enlarged Board of Appeal cases G 1/03 and G 1/16, a possible way of restoring novelty of an application in view of an accidental anticipation is to restrict the subject-matter not disclosed in the application as filed using an undisclosed disclaimer.

An anticipation is taken to be accidental if it appears from the outset that the anticipation does not relate to the invention. In addition, "from a technical point of view the accidental anticipation is so unrelated and remote that the person skilled in the art would never have taken it into consideration when working or making on the invention". Most importantly, the disclosure should be irrelevant for assessing inventive step.

Consequently, until recently, in order for a disclosure to be considered as an accidental anticipation, the following criteria would have to be met:

  1. Unrelated and remote from the invention and field of the invention
  2. Irrelevant for assessing inventive step

This traditional approach was questioned in the recent Technical Boards of Appeal case T1218/14, where it was identified that the above criteria may after all not be a set requirement but rather a "consequence of the criterion".

To summarise, in T1218/14, the patent in question EP1812548 related to a method of preparing a beverage (contacting the beverage with cross-linking enzymes). During the opposition period, based on D1 (relating to a method for processing wheat flour dough containing a cross-linking enzyme to produce a syrup) the patent was revoked for lack of novelty with the proprietor submitting auxiliary requests (including an undisclosed disclaimer).

What came as a surprise was the approach used by the Board of Appeal (BoA). Despite finding the prior art document unrelated to the invention and irrelevant for inventive step, it was found to not be irrelevant enough to be an accidental anticipation. Hence whilst D1 and EP1812548 related to "different field of investigation" (flour vs beverages), the BoA held that D1 nevertheless disclosed a beverage additive. Consequently, whilst D1 may not be relevant for beverages per se, it was relevant to the field of beverage additives and therefore did not meet the second requirement for an accidental anticipation.

Whilst this may be the first time the BoA has taken a different approach to the requirements of an accidental anticipation, we believe there are two key messages to take away from T1218/14. First, the threshold and test for what constitutes as an "accidental anticipation" is very high and second (a more subjective message), when considering inventive step , the BoA can take a broad view of the prior art documents that are relevant for inventive step purposes, i.e an Applicant seeking to protect a beverage should consider a broad range of prior art documents relating to food technology in their patentability search.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.