Methods of Medical Treatment

1Any process for the medicinal, surgical, curative, prophylactic, diagnostic, therapeutic or other treatment of human beings or any process for a similar treatment of animals to render them free from disease or to increase their economic value cannot be a subject matter of patent. The above provision will not allow Swiss claims to be filed for medical uses.

2In Allergan v Controller of Patents (2023) the Delhi High Court recorded that “Method claims are patentable in the US, whereas they are not patentable in India, by virtue of Section 3(i) of the Patents Act.” (para 12)

3In The Chinese University of Hong Kong v Assistant Controller of Patents & Designs (2023) the Madras High Court held that “each limb of Section 3(i) is distinct and self-contained”, and that “said pronoun is referable only to the last antecedent ‘animals’ and not to human beings” (para 22). In Natera v Assistant Controller of Patents and Designs (2025) and Sequenom v Controller of Patents (2025) the Delhi High Court held that “The phrase ’to render them free of disease or to increase their economic value’ qualifies only treatment of animals and not of human beings” (para 79).

4The Chinese University of Hong Kong held that “The common thread running through the following categories - medicinal, surgical, curative, prophylactic and therapeutic - is that they are clearly methods of treatment of human beings”, and that “The enumeration of multiple forms of treatment followed by the generic ‘or other treatment’ also indicates that the word ’treatment’ is intended to be construed widely” (para 23). The Court recorded that “treatment is provided not only to free/cure a person of disease but also for prophylactic purposes, to alleviate pain, prevent aggravation of or to better manage a condition or disorder” (para 22). Of the absence of a comma after “prophylactic” in the text of the provision, the Court held that “the Patents (Amendment) Act, 2002 (Act 38 of 2002) contains a comma after the word prophylactic but the comma was not placed within the quotation marks”, and that “the missing comma is no more than printer’s devil” (para 21).

6Natera held that “this exclusion was only intended to safeguard the autonomy and efficacy of the medical profession in delivering essential care, not to create a blanket bar on patent protection for all innovations relating to diagnosis or treatment” (para 73), and that “exclusions from patentability are to be applied narrowly and purposively, so as not to unduly stifle innovation in technical fields, particularly those that lie outside the direct domain of clinical medical practice” (para 74). The Court held that “The intention behind these provisions is clearly to provide immunity to medical practitioners, technicians, nursing attendants and other persons, who may be coming in contact with human beings or animals requiring diagnosis or treatment” (para 61). Sequenom (paras 61, 73, 74) and EMD Millipore v Assistant Controller of Patents and Designs (2025) (paras 59, 60) are on the same lines.

7Natera held that “A plain reading of Section 3(i) of the Act would also make it clear that the intention is to exclude process claims and not product claims” (para 75), and that “Products used for diagnosis or therapeutic purposes, including kits, equipment, machines, and physical products, which satisfy the conditions of patentability do not fall within the scope of exclusions under Section 3(i) of the Act and would hence be patentable” (para 79). Sequenom (paras 75, 79) and EMD Millipore (paras 61, 65) state the same position.

8Of the terms of the provision, Natera held that “‘Medicinal process’ would mean processes which are used for administration of medicines” but “would not include medicinal products, medicines, medical devices, or even patentable product by process inventions”. It further held that “‘Surgical process’ means a process of performing surgery. However, surgical tools, surgical implements including surgical methods using novel tools and implements would all be patentable”. The Court observed that “a process adopted by a medical practitioner for curing or healing a disease would not be patentable, but tools and products or novel patentable methods used for the same would not be excluded”.(para 79).

9Natera held that “Mere identification of the regimen for the use of certain medicines in a particular manner or frequency or form would be excluded from patentability” (para 79).

10In Hirotsu Bio Science v Assistant Controller of Patents and Designs (2026) the Delhi High Court held that “Both The Chinese University of Hong Kong (supra) and Natera Inc. and Anr. (supra) have clearly interpreted that Section 3(i) of the Act prohibits both in vivo and in vitro processes” (para 17). The diagnostic limb is discussed further in Diagnostic Methods and the In Vitro Question.

11In Geron v Assistant Controller of Patents and Designs (2026) the Delhi High Court held that “Section 3(i) of the Patents Act excludes treatment methods from patentability” (para 16), and that the claimed method, “even though it is an in vitro method since it forms part of the treatment, and also since Section 3(i) of the Patents Act does not distinguish between in vivo and in vitro diagnostic processes, squarely falls within the exclusion of treatment methods under said provision” (para 32).

12In Decco Worldwide Post Harvest Holdings B.V. v Controller of Patents and Designs (2023) the Calcutta High Court recorded that “The Amendment Act 38 of 2002 amended section 3(i) to remove ‘or plants’ from its scope” (para 10). In Syngenta Crop Protection v Assistant Controller of Patents (2024) the Delhi High Court held that “Clearly, the object of the amendment was to remove the bar on the patentability in respect of methods for the treatment of plants.” (para 19) Natera held that “Methods of treatment of plants are not covered by Section 3(i) of the Act and would be patentable so long as the test of Section 3(j) of the Act is satisfied” (para 79).