8.1.1 Definition

According to the case law of the boards of appeal (see e.g. T 1787/20), the person skilled in the art should be presumed to be an experienced practitioner who has average knowledge and abilities and who is aware of what the common general knowledge was in the relevant art concerned at a particular time (average skilled person). The skilled person should also be presumed to have had access to everything in the state of the art, in particular the documents cited in the search report, and to have had at their disposal the normal means and capacity for routine work and experimentation (EPC Guidelines G‑VII, 3 – April 2025 version). The skilled person will be an expert in a technical field (T 641/00, OJ 2003, 352). The board in T 39/93 (OJ 1997, 134) held that, whilst generally accepted definitions of the notional "person skilled in the art" did not always use identical language to define the qualities of such a person, they had one thing in common, namely that none of them suggested the skilled person was possessed of any inventive capability. It was the presence of such capability in the inventor which set them apart from the notional skilled person.

In T 1462/14 the board noted that the skilled person was a notional entity that had been elaborated on by the case law of the boards of appeal in order to serve as an objective reference when deciding on various issues under the EPC. This notional person could not be equated with any real person in the technical field of the invention. Neither an inventor, nor an opponent, nor an examiner, nor a member of a board of appeal, could be equated with the skilled person. This also applied to a representative.

With regard to the definition of the skilled person, the board in T 26/98 summarised the following principles which are generally applied by the boards of appeal: if the problem prompts the skilled person to seek its solution in another technical field, the specialist in that field is the person qualified to solve the problem (confirmed in T 1523/11, see also T 1787/20). The assessment of whether the solution involves an inventive step must therefore be based on that specialist's knowledge and ability (see decision T 32/81, OJ 1982, 225; T 141/87; T 604/89 of 15 November 1990 date: 1990-11-15; T 321/92; see also chapter I.D.8.3). The skilled person can also be expected to look for suggestions in neighbouring fields if the same or similar problems arise in such fields if they are aware of them (see chapter I.D.8.2). The skilled person can be expected to look for suggestions in a general technical field if he is aware of such fields. In advanced technical fields the competent "skilled person" could be taken to be a team of experts from the relevant technical branches (see chapter I.D.8.1.3). Solutions to general technical problems in non-specific (general) fields are considered to form part of the general technical knowledge (see chapters I.D.8.2 and I.D.8.3).

It is further established case law that it is the normal task of a skilled person working in a certain field not to remain inactive but to seek alternatives, to be constantly occupied with the elimination of deficiencies, with the overcoming of drawbacks and with the achievement of improvements of known devices and/or products (T 867/11; see also amongst others T 455/91, OJ  1995, 684; T 1102/00, T 247/11).

In T 1030/06 the application related to a system and method for securely buffering content. The board considered that the skilled person was a person of ordinary skill in the art which meant not only having access to the state of the art and common general knowledge in the field, but also the capability to perform routine work and experimentation. Thus, the skilled person could be expected to seek out solutions and make choices to try to solve design problems that crop up.

According to the board in T 1761/12, the position that the problem-solution approach developed through the boards' case law did not allow for considering whether or not it was necessary to retain features not differing from the closest prior art was too formalistic. Over and above the lack of imagination widely attributed to the skilled person, this position also seemed to deny them the capacity to draw conclusions from information obtained direct from the prior art.

According to T 422/93 (OJ 1997, 25), when examining for inventive step using the "problem and solution approach", the starting point for defining the appropriate skilled person was the technical problem to be solved on the basis of what the prior art disclosed, irrespective of any other definition of the skilled person suggested in the contested patent. Since the technical problem addressed by an invention had to be so formulated as not to anticipate the solution, the skilled person to be considered could not be the appropriate expert in the technical field to which the proposed solution belonged if this technical field was different to the one considered when formulating the technical problem. Nor did the appropriate skilled person's basic knowledge include that of a specialist in the different technical field to which the proposed solution belonged, if the closest prior art gave no indication that the solution was to be sought in this other technical field.

In T 25/13 the board stated that opponents were essentially free to choose the starting point for assessment (here D4), but their choice then had implications for the technical knowledge of the relevant skilled person. The board concluded that there were two options: either to take the skilled person in the field of the invention (motor vehicle) – who would never have consulted D4 (tumble dryers) because it was from a totally different field – or to take D4 as the starting point, in which case the skilled person's field would be domestic appliances and the solution would not be obvious to them.

In T 1924/20 the board highlighted that the description and drawings were typically used by the deciding body to determine the "skilled reader" and, hence, the viewpoint from which the claims are interpreted. See also II.A.6. "Interpretation of claims".