Enlarged Board decision G 2/88 (OJ 1990, 93) related to a change of claim category in opposition proceedings, and in particular to the change from a product claim to a use claim. It stated that a change of category of granted claims in opposition proceedings was not open to objection under Art. 123(3) EPC 1973, if it did not result in extension of the protection conferred by the claims as a whole, when they were interpreted in accordance with Art. 69 EPC 1973 and its Protocol. In this context, the national laws of the contracting states relating to infringement should not be considered, for there was a clear distinction between the protection which was conferred and the rights which were conferred by a European patent. The protection conferred by a patent was determined by the terms of the claims (Art. 69(1) EPC 1973), and in particular by the categories of such claims and their technical features. In contrast, the rights conferred on the proprietor of a European patent (Art. 64(1) EPC 1973) were the legal rights which the law of a designated contracting state might confer upon the proprietor. In other words, in general terms, determination of the "extent of the protection conferred" by a patent was a determination of what was protected, in terms of category plus technical features; whereas the "rights conferred" by a patent were related to how such subject-matter was protected.
When deciding upon the allowability of an amendment involving a change of category, the considerations were, in principle, the same as when deciding upon the allowability of any other proposed amendment under Art. 123(3) EPC 1973.
An amendment of granted claims directed to "a compound" and to "a composition including such compound", so that the amended claims were directed to "the use of that compound in a composition" for a particular purpose, was not open to objection under Art. 123(3) EPC 1973. For it was generally accepted as a principle underlying the EPC that a patent which claimed a physical entity per se, conferred absolute protection upon such physical entity, for all uses of such physical entity, whether known or unknown. It followed that if it could be shown that such physical entity (e.g. a compound) was already part of the state of the art, then a claim to the physical entity per se lacked novelty. It also followed that a claim to a particular use of a compound was in effect a claim to the physical entity (the compound) only when it was being used in the course of the particular physical activity (the use), this being an additional technical feature of the claim. Such a claim therefore conferred less protection than a claim to the physical entity per se.
In T 912/91 the appellant/patentee claimed the use of graphite for obtaining a sintered composite ceramic body having certain characteristics. The board held that the change of claim category from the granted product claims for composite bodies to these use claims did not broaden the scope of protection of the granted claims. Even if it were considered that the use claim was notionally equivalent to a claim to a process including the step of using the graphite in the sintered body and that the effect of Art. 64(2) EPC 1973 was to confer protection on the product resulting from this process as well, this would not represent an extension of protection within the meaning of Art. 123(3) EPC 1973, since the sintered composite body was defined in the use claim in a more restricted way than the composite body of the granted claim (narrower range of the graphite content, etc.).
In T 134/95 a patent had been granted in respect of a "container for medical use". The claimed apparatus was designed to permit the separate storage and the mixing, at the time of use, of three predefined and different compounds. The protection conferred therefore related to the apparatus and, necessarily, to its use at least for the purposes of storage and mixing. After amendment, the claim became a use claim, covering only the use of the container and no longer protecting the apparatus as such. Having pointed out that inventions of this kind were designed with a particular object in mind and could not normally be used for other purposes, the board noted that in this case, the change of category, replacing the granted claim with a claim for the use of the container, had the effect of limiting the scope of protection. The amendment was therefore allowable. The two stages of the process therefore in no way had the effect of modifying the starting solutions with a view to obtaining or manufacturing a product. This use therefore fell into the category "use of a physical entity to obtain an effect or result", and on this basis the change of category was allowable.
In T 279/93 the board found that a claim to the use of a compound A in a process for preparing compound B had no broader scope than a claim to a process for preparing compound B from compound A. It had already been stated in G 2/88 (point 2.5 of the Reasons) that the technical features of a claim to an activity were the physical steps which defined such activity. In this case, the board considered that process claim 1 as filed, process claim 1 as granted and use claim 1 filed on appeal all related to the same physical steps, and that the claims were therefore of the same scope. On this view, the scope of protection conferred by this use claim was not broader than that conferred by the granted process claim (see also T 619/88).
In T 420/86 a change from a claim for a process for treating soil, in which X was used, to a claim for the use of X for treating soil was allowed. In T 98/85 on the other hand, a change from a "process for the preparation of a ... composition" to the "use of this ... composition as a ..." was seen as a breach of Art. 123(3) EPC 1973.
In T 276/96 the board decided in view of G 5/83 (OJ 1985, 64) that the change of claim of the type "Method of fabricating item A using item B providing effect C" to a claim of the type "Use of item B in a method of fabricating item A to provide effect C" did not extend the protection conferred, since with both formulations the same activity would be forbidden to competitors.
A change from a product claim to a claim for a process for manufacturing the product is generally seen as unproblematic (T 54/90, T 191/90, T 762/90, T 153/91 and T 601/92). In T 423/89 the change in category from a product-by-process claim to a manufacturing process claim was admissible. In T 402/89, however, the board pointed out, in passing, certain difficulties in interpreting the term "protection conferred".
In T 5/90 the patent was granted with a claim in the form "a product having product features x and product-by-process features characteristic of process steps y". This claim, however, turned out not to be novel. The patentee finally claimed "a process of making a product having product features x by using process steps y and process steps z".
The board interpreted such a claim as covering the process steps only in so far as a product having product features x actually resulted. This was called a process-limited-by-product claim by the board. The direct product of this process would also be protected under the provisions of Art. 64(2) EPC 1973, but such product inevitably fell within the scope of the product claim originally granted. The board regarded a process-limited-by-product claim of this type as clearly complying with the requirements of Art. 123(3) EPC 1973 because it would only be infringed if the product fell within the originally granted product claim and in addition the particular form of manufacture using process steps z was used (decision cited in T 562/04).
In T 20/94 the patent in suit in the form as granted exclusively comprised process claims for preparing a product. In the form as amended it comprised a product claim relating to the product per se. The board stated that the protection conferred by a claim directed to a process for preparing a product covered that process. Pursuant to Art. 64(2) EPC 1973, a product directly obtained by that process was also protected, but it was not protected when obtained by any other process. However, the protection conferred by a claim directed to a product per se was absolute upon that product. The product claim thus conferred protection on that product regardless of the process by which it was prepared.
The appellant attempted to overcome this objection by formulating the product claim as amended in the form of a productbyprocess claim using the term "directly obtained". The board did not agree with this line of argument, stating that a productbyprocess claim was interpreted as a claim directed to the product per se, since the only purpose of referring to a process for its preparation was to define the subjectmatter for which protection was sought, which was a product. Whether or not the term "directly obtained" or any other term, such as "obtained" or "obtainable", was used in a productbyprocess claim, the category of that claim did not change. Thus amended claim 1 in the case in question contravened Art. 123(3) EPC 1973.
In T 426/89 (OJ 1992, 172) the claim related to a process for operating a pacemaker. An actual operating method for a pacemaker for arresting a tachycardia would necessarily be a method for treating the human (or animal) body by therapy using a pacemaker, and would not be patentable. However, the patentee maintained that the claim referred to the steps in a technical method which did not define a method of treatment but rather, in functional terms, the structural features of a pacemaker. The board agreed. If correctly interpreted in accordance with Art. 69(1), second sentence, EPC 1973 claim 1 did not define a method but rather an apparatus (pacemaker) in terms of the functions of its components. Since the reference to a method in the designation of the subject-matter of claim 1 did not make this explicit, the board regarded claim 1 as not "clear" within the meaning of Art. 84 EPC 1973. The differences between the patent according to the auxiliary request and the granted version were that in claim 1 the title of the invention, "Method for the operation of a pacemaker", had been replaced by "Pacemaker". The board pointed out that the amendment of claim 1, including its change of category, did not contravene Art. 123(3) EPC 1973. Claim 1 as granted was already a product claim containing a functional definition of a pacemaker. So the seeming change of category did not alter the content of the claim but simply served to clarify it (see also T 378/86, OJ 1988, 386).
In T 82/93 (OJ 1996, 274) the granted patent contained a claim 1 relating to a method of operating a pacer. The board found that this claim defined a method for treatment of the human body by therapy and therefore was not allowable under Art. 52(4) EPC 1973. It held that the device claim of the auxiliary request was not allowable under Art. 123(3) EPC 1973. The subject-matter protected by the granted claim was a pacer, when in use; in contrast, the claim of the auxiliary request only included technical features which defined physical characteristics of the pacer device itself. The board explained that in general terms, if a patent as granted only included claims defining the operation of a device and therefore containing both "device features" and "method features", and the proposals to amend the patent during opposition proceedings included claims which only contained "device features", the proposed amendment was not allowable having regard to Art. 123(3) EPC 1973, because the patent as granted conferred protection upon the device only when it was in use so as to carry out the method, whereas the proposed amended patent would confer protection upon the device whether or not it was in use, and would therefore confer additional protection compared to the patent as granted.
In contrast to the findings in T 426/89 mentioned above, in this case the board held that claim 1 as granted was clear, defined the use of a device to carry out a method of treatment of the human body by therapy and was not a pure "device claim" since it also included method steps. Thus, under such circumstances, Art. 52(4) and Art. 123(3) EPC 1973 might operate in combination as an "inescapable trap".
In T 1206/01 the board clearly pointed out that according to the established case law of the boards of appeal a product claim conferred protection on the claimed product, regardless of the process or method by which it was prepared. Therefore a change of category from a granted product claim to a process claim restricted to one or more methods of preparing the product did not extend the protection thereby conferred.
In T 352/04 the patent related to a hair-setting agent. The question arose whether the scope of protection had been extended by an amendment, and in particular by the addition of "with a mechanical spray device" in claim 1. The board drew attention to the jurisprudence, which says that the scope of the protection conferred by a patent is defined not only by its technical features but also by the category of the claims. It found that the inclusion of the mechanical spray device as a separate element in claim 1 also changed the claim category, which could now embrace a spray device containing the cosmetic agent. The amended claim 1, therefore, enabled not only a means patent (for hair treatment) but also an apparatus patent (mechanical spray device containing the cosmetic agent) to be given protection. The board further found that a mechanically driven spray device containing a cosmetic hair-treatment agent could not be regarded as either a process for manufacturing the hair-treatment agent or a (further) use of the agent, nor did it involve a category change which could be considered admissible under Art. 123(3) EPC 1973. On the contrary, the amendment of the claim shifted the patent proprietor's protection, at the cost of legal certainty for third parties, towards the inclusion of further, previously unprotected subject-matter, which however was precisely what Art. 123(3) EPC 1973 sought to prevent.
The board concluded that incorporating the feature "with a mechanically driven spray device" had brought within the scope of protection subject-matter which now also comprised, in addition to the cosmetic hair-treatment agents, a mechanical spray device in the most widely varied embodiments, since the scope of protection could not be limited to the wording of the claim. As the claim's amended wording now also protected a mechanical device not covered by the claim as granted, the scope of the protection conferred by the patent at issue had been extended vis-à-vis the hair-treatment agent as granted. The contested patent's text as maintained therefore contravened Art. 123(3) EPC 1973.
T 1635/09 (OJ 2011, 542) was concerned with the conversion of a use claim to the so-called Swiss form of claim. In this case, claim 1 in the 23rd auxiliary request differed from claim 1 in the granted text in that the originally granted use claim was converted to the so-called Swiss form of claim, in other words a claim for the use of a substance or mixture of substances for manufacturing a medicament for a specific therapeutic use. Under the established jurisprudence of the boards of appeal, the process of establishing whether the scope of protection was extended by this amendment must take all the granted claims into consideration. It was therefore necessary to determine whether the reformulation of a claim for the "use of an oral dosing form comprehensively ... for contraception ..." into a claim for the "use of a composition comprehensively ... for manufacturing an oral ... dosing form for contraception ..." complied with the requirements of Art. 123(3) EPC. A crucially important question here was whether the Swiss-type claim was to be regarded as for (a) the use of a substance or mixture of substances for a specific purpose or (b) the manufacture of a medicament. Citing G 5/83 (OJ 1985, 64) and G 2/88 (OJ 1990, 93), the board in T 1635/09 ruled that the conversion of a claim for the use of a substance or mixture of substances for a specific purpose into a Swiss-type claim or a product claim limited to a specific use in accordance with Art. 54(5) EPC results in an extension of the scope of protection.