6. Interpretation of claims

In T 1642/17 the sole reason for the application being refused was that it did not meet the requirements of Art. 84 EPC. In particular, the examining division held that certain definitions in a document cross-referenced in the description were essential to determine the boundaries of the claims and must be introduced into the description, which should be self-contained. It also referred to established case law that a patent document may be its own dictionary. The board understood the examining division’s objection to be that the claims lacked clarity when read and interpreted in the light of the description. However, it was established case law that where the claims and the terms used in them are clear when read on their own, for instance because they have a well-established meaning in the art, the unambiguous claim wording must be interpreted as it would be understood by the skilled person without the help of the description (see T 2221/10 and T 197/10; also Case Law of the Boards of Appeal, 9th ed. 2019, II.A.6.3.1). As set out in the latter decision, this applied in the event of a discrepancy between the claims and the description. In the case in hand, the board agreed with the examining division that the terms used in the claims had a "generally accepted meaning" to the skilled person. In view of this and the above case law, it concluded that the claims met the clarity requirements of Art. 84 EPC. It followed that the presence of a cross-reference in the description containing a definition of these terms should not be treated differently to a case where the description itself contains such a definition. In neither case would the effect of the definition of terms which already have a well-established meaning in the art have a negative effect on the clarity of the claims. Indeed, neither the description nor a cross-reference could change a generally accepted meaning of terms in a claim. The board also noted that the parallel drawn by the examining division to the case where the description has to be adapted to ensure compliance with Art. 83 EPC was incorrect, because Art. 84 EPC refers to the claims, whereas Art. 83 EPC refers to the disclosure of the patent application. Instead, to ensure that the application complied with the support requirement of Art. 84 EPC, the examining division could request that the description be adapted to be in line with the claims (see Case Law of the Boards of Appeal, 9th ed. 2019, II.A 5.3).

In T 1409/16 the board considered that both "exclusive disjunctions" and "inclusive disjunctions" could be expressed by the "either (...) or" wording. The fact that another expression ("and/or") was used (in the sense of an inclusive "or") in another claim of the contested patent was not, as such, a compelling reason for concluding that the "either (...) or" wording used in the claim in question must have a different meaning, i.e. that it expressed an exclusive "or". There was no absolute obligation to use a fully coherent terminology for expressing given features if the latter could be expressed in different ways. The board held that the "either (...) or" wording could only be considered as expressing an exclusive "or" in cases where the two situations referred to were, due to their very nature, mutually exclusive, i.e. incompatible with each other. See also chapter I.B.2.1. "Public prior use – internal structure or composition of a product".