In T 325/95 the patent proprietor amended a granted claim by introducing limiting features disclosed only in the description. The appellant (opponent) argued that claim 1 as granted did not actually afford any scope of protection whatsoever, because the claim was invalid, its subjectmatter lacking an inventive step. Since the features added to claim 1 were not set out in any of the dependent claims as granted, the subjectmatter now covered by amended claim 1 was not covered by any of the claims. Therefore, by introducing features disclosed only in the description the scope of the claims had been extended within the meaning of Art. 123(3) EPC 1973.
The board pointed out that this argumentation was based on the assumption that the extent of protection referred to in Art. 123(3) EPC 1973 would depend not only on the actual wording of the claims, but also on their validity in view of the prior art. This assumption however was not supported by the explicit statement in Art. 69 EPC 1973 that "the extent of the protection conferred by a European patent ... shall be determined by the terms of the claims". Appellant's submissions in effect also implied that claims amended in opposition proceedings should always have a counterpart in the set of claims as granted. This was not in line with the consistent case law of the EPO either. Attention was drawn for instance to decision G 2/88 (OJ 1990, 93), which ruled that replacement of a granted claim to a compound or composition by a claim directed to a new use of the compound or composition was admissible under Art. 123(3) EPC 1973.
In T 177/08, with reference to Art. 123(3) EPC, the board referred to Art. 69(1), second sentence, EPC, which provides that the description and the drawings are to be used to interpret the claims. The board said that it had therefore to be decided whether said interpretation of the claims by the content of the description was limited to cases where the claims were in need of interpretation, e.g. because of functional or unclear features, or whether it also applied to the case at issue, where a well-known and generally accepted meaning of a term was overthrown and replaced by a new definition given in the description. The appellant cited decisions T 1321/04 and T 190/99 in this context. In contrast to decision T 190/99, where a term used in its usual meaning did not make technical sense, formula II according to claim 1 of the contested patent did not include any subject-matter which was illogical or did not make technical sense if the term "alkyl" was used in its usual and well-known meaning. T 1321/04 was not concerned with the issue of determining the scope of protection but how a term should be interpreted in the assessment of novelty.
In T 177/08 the situation was that the meaning of the feature in question was generally accepted, perfectly understandable per se, and unambiguously defined by IUPAC, whom the skilled person acknowledged as the competent authority in this context. The skilled person therefore had no need to consult the description for a definition of "alkyl". The board was of the opinion that the second sentence of Art. 69 EPC did not apply to cases where an unambiguous and generally accepted definition of a term figuring in the claims was to be superseded by a different definition found in the description. If it was intended that a term which was in no need of any interpretation be given a new meaning, then the definition for this new meaning had to be put into the claims. Third parties could not be expected to check every single term of the claims for a potentially different meaning that might be hidden somewhere in the description. As a consequence, the board concluded that the subject-matter of the main request extended the protection conferred and did not meet the requirements of Art. 123(3) EPC.
In the case underlying T 547/08, the invention concerned dialysis machines with touch screen user interface. The board stated that the appellant/opponent's arguments relating to the rights of the patent proprietor to sue for indirect or contributory infringement were not relevant to the issue of extension of the scope of protection under Art. 123(3) EPC. In G 2/88 (OJ 1990, 93) it was clearly ruled that it is not necessary to consider the national laws of the contracting states in relation to infringement and that this issue is not relevant when deciding upon admissibility of an amendment under Art. 123(3) EPC. With respect to the question of an extension of the scope of protection under Art. 123(3) EPC, it is, rather, appropriate to take into account the fact that the protection conferred by a patent is determined by the terms of the claims, and in particular by the categories of the claims and their technical features, in accordance with Art. 69(1) EPC and its protocol (G 2/88, OJ 1990, 93). According to the latter, Art. 69 EPC should be interpreted as a compromise between fair protection for the patentee and a reasonable degree of legal certainty for third parties. The description and drawings may be employed to a certain extent to interpret the claims, rather than only for the purpose of resolving a possible ambiguity in the wording of the claims. Further, in the board's view, the decisions cited by the appellant to support its line of argument were not applicable to the situation. The case underlying T 352/04 related to a change from a substance to a combination of the substance and a device, which was regarded as a change of the claim category. In the case at issue, however, there was no such change of category. T 867/05 related to a change from "a membrane material for use in dialysis ...", i.e. a substance A for use in a method X, to "an artificial kidney in which there is used a membrane material...", i.e. a combination of a device B and the substance A, which was also a situation quite different from the case before the board. The appellant's argument that the scope of protection had been shifted to an "aliud", i.e. from a user interface and screen display apparatus to a dialysis machine, and was thus in breach of Art. 123(3) EPC, was not accepted by the board. The board observed that a change from a (granted) claim, directed to a first physical entity, to a second, more complex physical entity (an "aliud") in opposition proceedings is a common and usual procedure entirely in line with the requirements of Art. 123(3) EPC: adding one or more limiting technical features to a claimed device naturally renders the claimed entity more complex and results in a restriction rather than an extension of scope.
The invention in T 1172/08 concerned a process for the preparation of protein mutants having lower allergenic response in humans. The interpretation of the protection conferred by a patent according to Art. 69 EPC was in general not one of the duties of the boards of appeal (cf. T 175/84). For the purpose of establishing whether the amendments of the main request fell foul of the provisions of Art. 123(3) EPC, it was however necessary to do so. The board stated that it was evident, and not contested by the parties, that obtaining a solution of monocyte cells from a blood sample was not the same as obtaining a solution of dendritic cells from a blood sample. Thus, claim 1 as granted and claim 1 of the main request, when read on their own, provided protection for different subject-matter. Appellant I/patent proprietor agreed that normally such a shift in the extent of protection would not be allowable. It argued, however, that the case at issue was very particular because the claims as granted did not embrace the subject-matter of the only example of the patent specification. It had therefore to be established whether the amendments to claim 1 resulted in an extension of the scope of protection conferred by the patent as a whole. Appellant I concluded that what determined the scope of protection in the case at issue was not the literal meaning of the term dendritic cells. Since the literal meaning of the term dendritic cells was not consistent with Example 1, on a proper construction of claim 1, there was no extension of the scope of protection.
The board had no doubts and the parties did not dispute that dendritic cells and monocytes are different cell types characterised by different features. Both cell types can be distinguished by morphological features as well as phenotypic and molecular markers, and the isolation of enriched dendritic cell fractions from blood samples was for instance disclosed in prior-art document D8. Thus, the skilled person would a priori not have had any reason to read a different technical meaning into the term "obtaining from a blood sample a solution of dendritic cells". Reading appellant I's interpretation into claim 1 would require the skilled reader to completely ignore the wording of granted claim 1, which per se was not technically meaningless, with the consequence that the wording of claim 1 would merely serve as an empty shell. This was clearly not in the sense of Art. 69 EPC nor in the sense of the protocol on its interpretation. Moreover, the interest of third parties in legal certainty would be completely ignored, if appellant I's interpretation were found to be acceptable. The board came to the conclusion that the main request did not meet the requirements of Art. 123(3) EPC.
The decisions reported below, while likewise looking at the extent of protection, additionally address the notion of a cut-off point.