6.3. Using description and drawings to interpret the claims
6.3.2 Legal basis for using description and drawings to interpret the claims
Several decisions applying the principle whereby the description and drawings are used to interpret the claims refer to Art. 69(1) EPC 1973 (T 23/86, OJ 1987, 316; T 16/87, OJ 1992, 212; T 238/88, OJ 1992, 709; T 476/89; T 544/89; T 565/89; T 952/90; T 717/98). Other case law emphasises that Art. 69 EPC 1973 (Art. 69 EPC) and its Protocol are primarily for use by the judicial organs which deal with infringement cases (see e.g. T 1208/97, T 1279/04, T 223/05, T 1047/11, T 56/21). The board in T 556/02 made it clear that it applied solely the general principle of law applied throughout the EPC that a document had to be interpreted as a whole (see e.g. T 23/86; T 860/93, OJ 1995, 47). Art. 69 EPC 1973 was a specific application of this general principle. See also T 1871/09, T 1817/14, T 447/22.
In T 1279/04 the board did not share the appellant's (patent proprietor's) view that, for the purposes of assessing novelty in opposition proceedings, claims should be interpreted in accordance with Art. 69(1) EPC 1973 and the Protocol on its interpretation. Art. 69(1) EPC 1973 and its Protocol related to the extent of protection conferred by the patent or patent application, which was primarily of concern in infringement proceedings. They served to determine a fair protection – inter alia by reference to the description and drawings – in circumstances where the claim wording was set in stone. By contrast, in examination and opposition proceedings the value of future legal certainty was paramount. In this forum the function of the claims was to define the matter for which protection was sought (Art. 84, first sentence, EPC 1973). There was no case for anything other than a strict definitional approach (for an interpretation of this approach, see T 1534/12), given that in this procedural stage the claim could and should be amended to ensure legally certain patentability, in particular novelty and inventive step over any known prior art. Amendment rather than protracted argument should be the answer to genuine difficulties of interpretation in all aspects of the examination and opposition procedure, it being acknowledged that amendments to a patent as granted should be occasioned by grounds for opposition. See also T 145/14.
Likewise in T 1808/06 the board emphasised that, when the description has to be amended with regard to the requirement of Art. 84 EPC, it was only in situations where the removal of inconsistencies was not possible for procedural reasons (e.g. no amendment possible of the granted version) that – purely as an auxiliary construction – Art. 69(1) EPC could be invoked for an interpretation of the claimed subject-matter.
In T 1646/12 the board stressed that Art. 69(1) EPC concerned only the extent of protection, which in turn was relevant only for the purposes of Art. 123(3) EPC and in national infringement proceedings. A general requirement that claims be interpreted with the help of the description could not be derived from Art. 69(1) EPC. It was nevertheless a general principle that a term could be interpreted only in context. Terms in a claim therefore had to be interpreted in the overall context of the claims set and the description (see also T 1817/14). Two extremes had to be avoided. On the one hand, limiting features mentioned in the description but not in the claims could not be read into the latter (see in this chapter II.A.6.3.4). They could not be inserted this way through interpretation, but only by amending the claims. On the other hand, claims could not be considered in complete isolation from the description. The skilled person interpreting the claim had to at least ascertain whether the expressions used were to be understood in their ordinary literal sense or whether they had a special meaning defined in the description. Likewise, if the claims were obscure, the skilled person had no alternative but to search for clarification both in the other claims and in the description and drawings (see in this chapter II.A.6.3.3). Using the description to interpret the claims was therefore admissible within certain limits, and sometimes even necessary; there was no need to invoke Art. 69(1) EPC.
In T 1473/19 the board disagreed with the findings in T 1279/04 and held that Art. 69 EPC in conjunction with Art. 1 of its Protocol can and should be relied on when interpreting claims and determining the claimed subject-matter in proceedings before the EPO, including for the purpose of assessing compliance with Art. 123(2) EPC. According to the board, interpreting the claimed features for the purposes of establishing the (first part of a) patent claim's extent of protection was not different from interpreting and determining the claimed subject-matter for the purposes of assessing compliance with Art. 54, 56, 83 and 123(2) EPC. Moreover, the general application of Art. 69 EPC and its Protocol in proceedings before the EPO was also required to ensure uniform and consistent claim interpretation, if for example the relevant feature needed to be interpreted not only under Art. 123(3) EPC but – as in the underlying case – also under Art. 123(2) EPC. The board pointed out that national courts applied the rules for the interpretation of claims in Art. 69 EPC and the Protocol in both infringement and revocation proceedings. In addition, the board agreed with the view in decisions T 2007/19, T 1646/12 and T 556/02 that it was a general principle that a term could be interpreted only in context, so that terms in a claim had to be interpreted in the overall context of the claims set and the description. Nevertheless, in T 1473/19 the board also stressed that the primacy of the claims according to Art. 69(1), first sentence, EPC limits the extent to which the meaning of a certain claim feature may be affected by the description and the drawings. Decision T 1473/19 was fully endorsed in T 450/20, T 1494/21 and T 367/20. The latter included several decisions of national courts in the contracting states as examples of national case law on claim interpretation according to Art. 69 EPC in respect of revocation proceedings.
In T 169/20 the board disagreed with the findings in T 1473/19 that Art. 69(1) EPC, in conjunction with Art. 1 of the Protocol, applies to the interpretation of the claims for the purpose of assessing patentability. The board held that the provisions in Art. 84 EPC and R. 42 and 43 EPC provided an adequate legal basis for claim interpretation when assessing the patentability of an invention. In particular, the requirement that the claims shall be "supported by the description" in Art. 84, second sentence, EPC provided a direct and unambiguous indication of the description's function as an aid for understanding the subject-matter of the claims.
According to the board in T 438/22, it is a general and overarching objective, and as such also a "requirement" of the EPC, that authorities, courts and the public interpreting the claims at a later stage should, as far as possible, arrive at the same understanding of the claimed subject-matter as the EPO bodies deciding on its patentability. The only tool for achieving this objective is the patent specification as the expression of a unitary legal title. The description, as an integral part of the patent specification, should therefore also serve this overriding objective, i.e. it should provide a common understanding and interpretation of the claims.
The application of Art. 69(1), second sentence, EPC and Art. 1 of the Protocol on the Interpretation of Article 69 EPC to the interpretation of patent claims when assessing the patentability of an invention under Art. 52 to Art. 57 EPC is addressed in the first question referred to the Enlarged Board in G 1/24 (see in this chapter II.A.6.3.1).
See also in this chapter II.A.6.3.4 "Reading additional features and limitations into the claims".
- G 0001/24
In G 1/24 the Enlarged Board ("EBA") considered the points of law referred to it by Technical Board of Appeal 3.2.01 in T 439/22 of 24 June 2024. The first question was whether Art. 69(1), second sentence, EPC and Art. 1 of the Protocol on the Interpretation of Article 69 EPC are to be applied to the interpretation of patent claims when assessing the patentability of an invention under Art. 52 to 57 EPC. The second question concerned whether the description and figures are to be consulted when interpreting the claims to assess patentability and, if so, whether this may be done generally or only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation. The third and final question was whether a definition or similar information on a term used in the claims, which is explicitly given in the description, can be disregarded when interpreting the claims to assess patentability and, if so, under what conditions.
The EBA confirmed that the departments of the EPO were required to interpret patent claims when assessing the patentability of an invention under Art. 52 to 57 EPC. As regards Question 1, the EBA held that there was no clear legal basis, in terms of an article of the EPC, for claim interpretation when assessing patentability. Article 69 EPC and Art. 1 of the Protocol were arguably only concerned with infringement actions and therefore were not entirely satisfactory as a basis for claim interpretation when assessing patentability. Article 84 EPC could also be criticised as an alternative legal basis as it addresses the content of the patent application and is formal in nature without providing guidance on how to interpret claims. It only sets out an instruction to the drafter of what needs to be in the claims and an instruction to the EPO to determine whether the claims meet that purpose. The EBA considered, however, that there was an existing body of case law of the Boards of Appeal which applied the wording of the aforementioned provisions in an analogous way to the examination of patentability under Art. 52 to 57 EPC, and from which the applicable principles of claim interpretation could be extracted.
The EBA further held it a settled point in the case law of the Boards of Appeal that the claims are the starting point and the basis for assessing the patentability of an invention under Art. 52 to 57 EPC.
As regards Question 2, the EBA stated that the description and any drawings must always be consulted when interpreting the claims, and not just in the case of unclarity or ambiguity. In adopting this position, the EBA rejected the case law of the Boards of Appeal that sees no need to refer to the descriptions and drawings when interpreting a claim, unless the claim is unclear or ambiguous. It found that this case law was contrary to the wording, and hence the principles, of Art. 69 EPC. It was also contrary to the practice of both the national courts of the EPC contracting states and the UPC. Moreover, from a logical point of view, the finding that the language of a claim is clear and unambiguous was an act of interpretation, not a preliminary stage to such an interpretative act.
Question 3 was held inadmissible by the EBA, which considered it to be encompassed by Question 2.
The EBA also referred to the harmonisation philosophy behind the EPC and noted that the case law of the UPC Court of Appeal on claim interpretation appeared to be consistent with the above conclusions. It further highlighted the importance of the examining division carrying out a high quality examination of whether a claim fulfils the clarity requirements of Art. 84 EPC, and stated that the correct response to any unclarity in a claim was amendment.
The order by the EBA in G 1/24 reads as follows: "The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57 EPC. The description and drawings shall always be consulted to interpret the claims when assessing the patentability of an invention under Articles 52 to 57 EPC, and not only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation."