The meaning of the term "treatment by surgery" is not to be interpreted as being confined to surgical methods pursuing a therapeutic purpose (see G 1/07, Reasons 3.3.10). Accordingly, the term "surgery" defines the nature of the treatment rather than its purpose. Thus, for example, a method of treatment by surgery for cosmetic purposes or for embryo transfer is excluded from patentability, as well as surgical treatment for therapeutic purposes. The term "treatments by surgery" further covers interventions performed on the structure of an organism by conservative ("closed, non-invasive") procedures such as repositioning or by operative (invasive) procedures using instruments.

Whether a claimed method is to be considered as surgical treatment falling under the exception of Art. 53(c) should be assessed on a case-by-case basis, taking the individual merits of each case into account. The reason for the exception is to allow medical and veterinary practitioners to use their skills and knowledge of the best available treatments to achieve the utmost benefit for their patients uninhibited by any worry that some treatment might be covered by a patent (see G 1/07, Reasons 3.3.6).

Thus, any definition of the term "treatment by surgery" must cover the kind of interventions which constitute the core of the medical profession's activities i.e. the kind of interventions for which their members are specifically trained and for which they assume a particular responsibility (G 1/07, Reasons 3.4.2.3).

The exclusion applies to substantial physical interventions on the body which require professional medical expertise to be carried out and which entail a substantial health risk even when carried out with the required professional care and expertise. The health risk must be associated with the mode of administration and not solely with the agent as such (G 1/07, Reasons 3.4.2.3). Examples of excluded treatments by surgery are the injection of a contrast agent into the heart, catheterisation and endoscopy.

Invasive techniques of a routine character which are performed on uncritical body parts and generally carried out in a non-medical, commercial environment are not excluded from patentability. They include e.g. tattooing, piercing, hair removal by optical radiation and micro-abrasion of the skin.

Similar considerations apply to routine interventions in the medical field. Thus, uncritical methods involving only a minor intervention and no substantial health risks, when carried out with the required care and skill, do not fall under the scope of Art. 53(c). This narrower understanding of the exclusion still protects the medical profession from the concerns indicated above. An example is a method for retraction of the sulcus of a tooth using a paste and a cap to prepare an impression of the tooth to manufacture a dental crown: the possible damage is limited to the superficial epithelium, the only risks are the superficial bleeding and inflammation which rapidly heal and the specific training needed to perform the method is minimal.

The required medical expertise and the health risk involved may however not be the only criteria which may be used to determine that a claimed method actually constitutes "treatment by surgery" within the meaning of Art. 53(c). Other criteria, such as the degree of invasiveness or the complexity of the operation performed, could also determine that a physical intervention on the human or animal body constitutes such treatment (see G 1/07, Reasons 3.4.2.4).

The exclusion under Art. 53(c) applies to multi-step methods which comprise or encompass at least one surgical step, as defined in the previous paragraph. The non-patentable subject-matter must be removed from the scope of the claim. This may be done either by means of a disclaimer or by omitting the surgical step from the wording of the claim (G 1/07, Reasons 4.2.2). For the general principles governing disclaimers, see H‑V, 3.5, and H‑V, 4. The overall patentability of the amended claim will however depend on its compliance with the other requirements of the EPC, which are assessed on a case-by-case basis.

If a surgical method claim is open to objection under Art. 53(c), this also applies to a corresponding claim directed to a computer-assisted surgical method. In other words, surgical methods for which European patents cannot be granted according to Art. 53(c) do not avoid exclusion merely through computer assistance.

Finally, when interpreting the scope of the exclusion under Art. 53(c), no distinction is to be made between human beings and animals.