Technical character results either from the physical features of an entity or (for a method) from the use of technical means. While an invention as a whole may possess technical character, it may nevertheless legitimately include both technical and non-technical features (T 641/00, OJ 2003, 352, T 1543/06). Mixed inventions are inventions having both technical and non-technical features, where "non-technical" relates to matter which, under Art. 52(2) EPC, is not to be regarded as an invention within the meaning of Art. 52(1) EPC.
In T 769/92 (OJ 1995, 525) (cf. also T 258/03, OJ 2004, 575) the board held that non-exclusion from patentability cannot be destroyed by an additional feature which as such would itself be excluded, as in the case before it features referring to management systems and methods which may fall under the "methods for doing business" excluded from patentability under Art. 52(2)(c) and (3) EPC 1973. This followed established case law according to which a mix of features, some of which are excluded under Art. 52(2) and (3) EPC 1973 and some of which are not so excluded, may be patentable (in contrast to case law concerning inventions excluded by Art. 52(4) EPC 1973, see T 820/92, OJ 1995, 113, according to which one feature excluded under Art. 52(4) EPC 1973 suffices for the whole claim to be excluded from patentability).
In T 26/86 (OJ 1988, 19) the board held that an invention must be assessed as a whole. If it made use of both technical and non-technical means, the use of non-technical means did not detract from the technical character of the overall teaching. The EPC does not prohibit the patenting of inventions consisting of a mix of technical and non-technical elements. The board therefore regarded it as unnecessary to weigh up the technical and non-technical features in a claim in order to decide whether it related to a computer program as such. If the invention defined in the claim used technical means, its patentability was not ruled out by Art. 52(2)(c) and (3) EPC 1973 and it could be protected if it met the requirements of Art. 52 to 57 EPC 1973 (cf. also T 209/91).
In T 603/89 (OJ 1992, 230) the board held that the subject-matter of a "mix" claim was not excluded from patentability under Art. 52(2) and (3) EPC 1973 when, but only when, the non-technical elements interacted with the known technical elements in order to produce a technical effect. Thus, the board considered that when there was an interaction between the technical and non-technical elements, and the mix as a whole solved a technical problem, it was not excluded from patentability (see T 26/86, OJ 1988, 19). In the absence of such an interaction - when the technical elements were only a support for the non-technical elements but did not otherwise co-operate therewith - the invention did not make use of technical means and could not therefore be granted (see T 158/88, OJ 1991, 566).
According to T 208/84 (OJ 1987, 14), one indication of technical character is that the method has an overall technical effect, such as controlling some physical process (see also T 313/10). In this decision the board held that, even if the idea underlying an invention may be considered to reside in a mathematical method, a claim directed to a technical process in which the method is used does not seek protection for the mathematical method as such.
In G 1/04 (OJ 2006, 334) the Enlarged Board of Appeal referred to T 603/89 (OJ 1992, 230) and found that the subject-matter of a claim including technical and non-technical features may satisfy the requirements of Art. 52(1) EPC 1973 if the non-technical features interact with the technical features in order to bring about a technical effect. It stated that, since the diagnostic methods referred to in Art. 52(4) EPC 1973 were inventions within the meaning of Art. 52(1) EPC 1973, it followed that, in a situation where the deductive medical or veterinary decision phase was a purely intellectual exercise, i.e. a step of a non-technical nature, such a method must necessarily further include preceding steps of a technical nature, in order to satisfy the requirements of Art. 52(1) EPC 1973.
In G 3/08 (OJ 2011, 10) the Enlarged Board of Appeal stated that it is in fact a well-established principle that features which would, taken in isolation, belong to the matters excluded from patentability by Art. 52(2) EPC may nonetheless contribute to the technical character of a claimed invention, and therefore cannot be discarded in the consideration of the inventive step. This principle was already laid down, albeit in the context of the so-called "contribution approach", in one of the earliest decisions of the boards of appeal to deal with Art. 52(2) EPC, namely T 208/84 (see also T 1784/06).