In T 116/85 (OJ 1989, 13) the board held that a claimed method was excluded from patentability, if it rendered the therapeutic treatment of animals necessary, even though the therapeutic treatment of animals was commonly an aspect of agriculture, and agricultural methods were in general potentially patentable subject-matter. Here, however, the board did not consider it possible as a matter of law to draw a distinction between such a method as carried out by a farmer and the same method when carried out by a veterinarian, and to say that the method, when carried out by a farmer, was an industrial activity and, when carried out by a veterinarian, was a therapeutic treatment and thus not patentable.

According to T 780/89 (OJ 1993, 440) the secondary effect of a therapeutic treatment did not render it patentable. The claim in question related to a method of general immunostimulation for animals. The applicant argued, inter alia, that this served to increase meat production and that the method was therefore not being used as a means of therapy. However, the board regarded the effect of increasing meat production as a consequence of the improvement in the animals' health. Moreover, the general stimulation of the immune system was integrally linked to the specific prophylactic function of safeguarding against particular infections.

In T 438/91 the patentee contended that the main purpose of the claimed process was to increase the weight of the animals which effect was separable from the effect of prevention or cure of scours. This latter was merely a beneficial side effect. It was necessary to decide whether or not a method for breeding domestic animals in claims 1 and 2 related to a therapeutic or prophylactic treatment. The board noted that two effects were observed as a result of the breeding method claimed: (a) the remedying of scours and, (b) a weight increase in the animals being bred. The board found that, in the light of the patent disclosure, the two effects were linked by the single action of feeding the animals, and that the intention was to obtain both effects at the same time in animals suffering from scours (treatment by therapy) and to prevent the latter complaint in those animals which did not already have it (treatment by prophylaxis). In conclusion, the board was of the opinion that the subject-matter of claims 1 and 2 related to a therapeutic or prophylactic treatment of domestic animals and thus fell within the prohibition on patentability set out in Art. 52(4) EPC 1973.

In T 290/86 (OJ 1992, 414) no method claim was considered allowable because the disclosed method of eliminating plaque inevitably had the therapeutic effect of preventing caries and periodontal disease; it therefore fell under the prohibition of Art. 52(4) EPC 1973 (now Art. 53(c) EPC) irrespective of the fact that the removal of plaque could also have the cosmetic effect of improving the appearance of the teeth. The board took the view that whether or not a claimed invention was excluded from patentability under Art. 52(4) EPC 1973 depended in particular on the wording of the claim in question. If the claimed invention was not directed solely to a cosmetic effect, but was also necessarily defining a treatment of the human body by therapy as well, such a claim was excluded from patentability (distinguishing T 144/83, OJ 1986, 301). The board held that if the claimed use of a chemical product inevitably always had a therapeutic effect as well as a cosmetic effect the invention as claimed necessarily defined a treatment of the human body by therapy and was not patentable (see also T 475/12).

In T 1077/93 claims 1 and 11 related to the use of the cupric complex of 3,5-Diisopropyl salicylic acid (referred to in the following as CuDIPS) as a cosmetic product or in a cosmetic composition, and to a cosmetic treatment process, based on the use of this complex, for the protection of the human epidermis. The purpose of the patented composition was to protect the human epidermis against ultraviolet radiation: notably, to reduce the intensity of erythema, recognised as the most spectacular form of damage to the skin by sunlight, and of skin-level cellular changes such as the formation of degenerated and necrotised keratinocytes, generally known by the term "sunburn cells (SBC)". In its ruling, the board cited the point, already explored in T 820/92 (OJ 1995, 113), that the exclusion of therapeutic methods from patentability could not be avoided by a purely formal rewording of the claim to qualify the purpose of the process, in its indivisible entirety, as non-therapeutic. The board took the view that the examination as to patentability of claims 1 and 11 necessitated an examination of the mechanism by which CuDIPS acted, and of the relationship between all its effects. The board concluded that at least part of the protective effect did not derive from a simple filtering at the level of the skin surface, but rather from an interaction with the cellular mechanisms in the epidermis, with the purpose of preventing a pathological state (erythema); therefore the process had a genuine therapeutic effect.

According to T 1635/09 (OJ 2011, 542) use as an oral contraceptive of a composition in which the claimed concentrations of the hormone content are selected at such a low level as to prevent or reduce the likely pathological side-effects of such an oral contraceptive is a therapeutic method excluded from patentability under Art. 53(c) EPC. The board held that the prevention of side‑effects – which was affirmed in claim 1 by the indication of the concentrations of active substance and which, in the light of the pathological nature of the secondary effects, clearly had to be classed as therapeutic – was inseparably associated with the per se non-therapeutic contraceptive process.

In T 158/13 it was not possible to distinguish between a therapeutic or non-therapeutic use of the stimulative perfume composition, since the way of administering the composition was the same for a therapeutic and a non-therapeutic use. Sleepiness or inactivity in daily life may not only be a physiological condition, but may also arise from a pathological condition. Without a clear and unambiguous distinction between a physiological and a pathological nature of a person’s mental condition, a clear distinction between therapeutic and non-therapeutic use is also impossible.