R. 42(1)(f) EPC (former R. 27(1)(f) EPC 1973) prescribes that the description should "indicate explicitly, when it is not obvious from the description or nature of the invention, the way in which the invention is industrially applicable".

In T 1452/06 the board stated that a basic principle of the patent system was that exclusive rights could only be granted in exchange for a full disclosure of the invention, which included the need to indicate how to exploit the invention (Art. 57 EPC 1973). This indication must have "a sound and concrete technical basis", as a "speculative indication of possible objectives that might or might not be achievable by carrying out further research with the tool as described was not sufficient to fulfil of the requirement of industrial applicability" (see T 898/05, T 870/04 and T 1109/10).

In T 898/05 the board found that for the purposes of Art. 57 EPC 1973, a claimed invention had to have such a sound and concrete technical basis that the skilled person could recognise that its contribution to the art could lead to practical exploitation in industry. The board explained that while industrial applicability should be construed broadly, to include any "immediate concrete benefit", this also entailed the need to disclose in definite technical terms the purpose of the invention and how it could be used in industrial practice to solve a given technical problem, this being the actual benefit or advantage of exploiting the invention. There had to be at least a prospect of a real as opposed to a purely theoretical possibility of exploitation, if it was not already obvious from the nature of the invention or from the background art. It should not be left to the skilled reader to find out how to exploit the invention by carrying out a research programme.

Accordingly, a product whose structure was given (e.g. a nucleic acid sequence) but whose function was undetermined or obscure or only vaguely indicated might not fulfil the above criteria, in spite of the fact that the structure of the product per se could be reproduced (made) (see T 870/04). If a patent was granted, it might prevent further research in that area. On the other hand, a product which was definitely described and plausibly shown to be usable, e.g. to cure a rare or orphan disease, might be considered to have a profitable use or concrete benefit, irrespective of whether it was actually intended for the pursuit of any trade at all.

In T 1450/07 the board referred to the principles established in T 898/05 that industrial applicability is acceptable if the disclosure in the application as filed on the function of a claimed compound (i) is plausible to the skilled person, (ii) is later confirmed by post-published evidence, and (iii) provides a clear basis for an industrial application.

In T 870/04 the board stated that a "practical" application of the invention had to be disclosed. Merely because a substance could be produced in some ways did not necessarily mean that this requirement was fulfilled, unless there was also some profitable use for which the substance could be employed.

The board noted that biotechnological inventions were quite often concerned with substances found in nature (e.g. a protein, a DNA sequence, etc.). If a function was well known to be essential for human health, then the identification of the substance having this function would immediately suggest a practical application in the case of a disease or condition caused by a deficiency, as was the case, for example, for insulin, human growth hormone or erythropoietin. In such cases, an adequate description would ensure that "the invention can be made or used in industry". In cases where a substance, naturally occurring in the human body, was identified, and possibly also structurally characterised and made available through some method, but either its function was not known or it was complex and incompletely understood; no disease or condition had yet been identified as being attributable to an excess or deficiency of the substance; and no other practical use was suggested for the substance, then industrial applicability could not be acknowledged. Even though research results may be a scientific achievement of considerable merit, they are not necessarily an invention which can be applied industrially.

In cases T 338/00 and T 604/04 the boards found the inventions industrially applicable despite the absence of actual experimental data, because a profitable use could readily be identified on the basis of the description, taking into account common general knowledge. Thus each case is decided on its own merits according to the particular technical circumstances, including extent of disclosure, background art and post-published evidence.

In T 641/05 the board considered that no actual information regarding the function of the CEGPCR1a clone at any of the three particular levels of function referred to in decision T 898/05, i.e. molecular, cellular and biological function in a broad sense (binding of a ligand, propagation of a transmembrane signal, role in a transduction signal pathway and/or in a network of interconnected pathways of a multicellular organism), could be directly derived from the application itself or from the prior art on file. Although, under certain conditions, the board was well prepared – following the case-by-case approach adopted in decision T 898/05 – to acknowledge a possible function based on computer-assisted methods, in the case before it the probative value of these (sequence homology) methods was completely lacking. In the absence of this functional information, no "immediate concrete benefit" in the sense defined in decision T 898/05 could be recognised for the CEGPCR1a clone disclosed in the application.

In T 1452/06 the board commented that the basis for all the therapeutic indications of the claimed subject-matter was the predicted role of the purported serine protease activity of the polypeptide of sequence SEQ ID NO: 24 in the degradation of the extracellular matrix. No experimental evidence whatsoever was present in the application in support of a serine protease activity for a polypeptide comprising the amino acid sequence of SEQ ID NO: 24. There was no example disclosing this serine protease activity, nor any evidence showing that the screening methods and the therapeutic indications based on this serine protease activity could actually be achieved with a polypeptide of sequence SEQ ID NO: 24. The only use of a polypeptide of sequence SEQ ID NO: 24 was to find out more about the polypeptide itself and its natural function(s); this was a speculative outcome and therefore provided no "immediate concrete benefit" (T 898/05, T 870/04).