e) Construction with regard to all technically logical interpretations 

In T 1408/04 the board held that while the claims had to be interpreted by a "mind willing to understand" and not by "a mind desirous of misunderstanding", this was understood to mean only that technically illogical interpretations should be excluded (see T 190/99). The terms to be interpreted had a wider technical interpretation than envisaged by the appellant. A "mind willing to understand" did not require that a broad term needed to be interpreted more narrowly (even if the narrow interpretation referred to a structure which was very common, but not exclusive, in the technical field concerned), but instead that a broad term should be interpreted with regard to all technically logical interpretations thereof. Based on this understanding of the limiting terms introduced into the claim the board came to the conclusion that the amendment to claim 1 as granted resulted in an intermediate generalisation.

In T 241/13 the board held that the description did not give a precise definition of the meaning of the expression "minimum intensity level"; the patentee's interpretation of this expression was not clearly excluded. However, that such an ambiguous expression as filed might be interpreted in a particular way was not sufficient to ensure the compliance of an amendment, based on that interpretation, with Art. 100(c) EPC which required a direct and unambiguous disclosure in the application as filed.

In T 1791/16 the board held that, in the interest of legal certainty, all technically reasonable interpretations of an ambiguous claim had to be considered. If one of those interpretations contained matter that extended beyond the content of the application as originally filed, it had to be concluded that there was added subject-matter.