6.3. Using description and drawings to interpret the claims
6.3.1 General principles
This section has been updated to reflect case law and legislative changes up to 31 December 2023. For the previous version of this section please refer to the "Case Law of the Boards of Appeal", 10th edition (PDF). |
The subject-matter of claims is governed by Art. 84 EPC and their function by Art. 69 EPC. According to Art. 84 EPC the claims define the invention for which protection is sought. According to Art. 69 EPC the claims determine the extent of the protection which will be conferred by the patent, through their definition of the invention. Under Art. 69 EPC the description and drawings are used to interpret the claims. The question arises whether it is possible to interpret the claims in the light of the description and drawings as provided in Art. 69 EPC merely in order to determine the extent of protection or whether it is also possible to do so in order to establish whether the conditions governing patentability and clarity have been satisfied.
In a number of decisions, such as T 23/86 (OJ 1987, 316), T 16/87 (OJ 1992, 212), T 327/87, T 89/89, T 121/89, T 430/89, T 476/89, T 544/89, T 565/89, T 952/90, T 439/92, T 458/96, T 717/98, T 1321/04, T 1433/05 and T 2145/13, the boards of appeal have laid down and applied the principle whereby the description and drawings are used to interpret the claims and identify their subject-matter, in particular in order to judge whether it is novel and not obvious. Likewise, in a large number of decisions (e.g. T 238/88, OJ 1992, 709; T 416/88; T 194/89; T 264/89; T 472/89; T 456/91; T 606/91; T 860/93; T 287/97; T 250/00; T 505/04), the boards interpreted the claims in the light of the description and drawings in order to establish whether they were clear and concise within the meaning of Art. 84 EPC 1973.
Occasionally, however, the limits to interpretation in the light of the description and drawings are emphasised (see in this chapter II.A.6.3.4). A discrepancy between the claims and the description is not a valid reason to ignore the clear linguistic structure of a claim and to interpret it differently (T 431/03) or to give a different meaning to a claim feature which in itself imparts a clear credible technical teaching to the skilled reader (T 1018/02, T 1395/07, T 711/14, T 1456/14, T 2769/17, T 169/20, T 821/20, T 42/22). In T 1023/02, though, "unfortunate" claim language ("transcription" instead of "translation") in contradiction with the description of the invention was interpreted differently.
In T 197/10 the board explained that if the claims are worded so clearly and unambiguously as to be understood without difficulty by the person skilled in the art, there is no need to use the description to interpret the claims. In the event of a discrepancy between the claims and the description, the unambiguous claim wording must be interpreted as it would be understood by the person skilled in the art without the help of the description. Thus, in the event of a discrepancy between clearly defined claims and the description, those elements of the description not reflected in the claims are not, as a rule, to be taken into account for the examination of novelty and inventive step. See, similarly, T 1514/14 concerning the examination of sufficiency of disclosure.
In T 2221/10 the board referred to established case law according to which the description can be used as the patent's "dictionary" to assess the correct meaning of ambiguous terms used in claims (see in this chapter II.A.6.3.3). The board, however, also referred to T 197/10, pointing out the limits to the interpretation in the light of the description and drawings. See also T 2328/15 and T 1642/17.
In T 1924/20 the board stated that a skilled reader of a patent claim would, for many reasons, interpret the claims based essentially on their own merits (see e.g. T 2764/19 and T 1127/16). This was because the "subject-matter of the European patent" is defined by the claims and only by them. The board explained that the description and drawings were, however, typically used by the deciding body to determine the above-mentioned "skilled reader" and, hence, the viewpoint from which the claims are interpreted. This meant that, when interpreting the claims, the description and drawings could not be relied on as a sort of fall-back or supplementary-guidance tool for filling up gaps or for resolving inconsistencies in a claim to the patent proprietor's advantage. Such a reliance on the description and the drawings by the patent proprietor would normally fail to convince.
In T 409/97 the board held that an erroneous statement in the introduction to the description, according to which a process according to the general part of claim 1 was known from a prior art document D1, was of no assistance in interpreting the claim and establishing the subject-matter for which protection was being sought, where this statement contradicted the actual content of D1.
- T 447/22
Catchword:
1. On the limits of claim interpretation in the light of the description (see point 13 of the reasons). 2. In application of decision G 3/14, an objection under Article 84 EPC that a claim is not supported by the description is open to examination in opposition or opposition appeal proceedings only when, and then only to the extent that, the lack of support has been introduced by an amendment to the patent. It must thus be accepted that the removal of an inconsistency between the description and a claim amended in opposition or opposition appeal proceedings is not possible when the inconsistency previously existed in the patent as granted (see point 83 of the reasons).
- T 1628/21
Catchword:
With regard to the question of compatibility of certain principles of claim interpretation for the purposes of considering novelty or inventive step with Article 69 EPC, reference is made to Reasons 1.1.11 to 1.1.16. The principle of primacy of the claims seems to exclude the use of the description and drawings for limiting the claims if an interpretation of the claim in the light of common general knowledge already leads to a technically meaningful result. Similarly, the principle, established by case law, according to which "limiting features which are only present in the description and not in the claim cannot be read into a patent claim" is also fully compatible with Article 69 EPC and Article 1 of the Protocol.
- 2023 compilation “Abstracts of decisions”