Natera Inc v Assistant Controller of Patents and Designs (2025)

Summary

“The present appeal involves an interpretation of the exclusions from patentability in respect of diagnostic methods under Section 3(i) of the Patents Act, 1970 (hereinafter ’the Act’).” (para 2) “The appeal has been filed under Section 117A of the Act, challenging the impugned order dated 20th March, 2023 passed by the Respondent – Assistant Controller of Patents and Designs.” (para 3) “Vide the impugned order the Respondent has refused the Patent Application bearing No. 201817033216 (hereinafter ’the subject patent application’) for the invention titled ‘Methods for Lung Cancer Detection’ ... while holding that Claims 1 to 4 thereto are not patentable under Section 3(i) of the Act. Further, Claims 5 to 8 of the subject patent application have been rejected in view of Section 59 of the Act.” (para 4) The Court described the subject invention as “a non-invasive, in vitro method to detect and monitor genetic mutations associated with lung cancer, specifically lung squamous cell carcinoma, using blood samples” (para 81).

The Court 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), that “the intention is to exclude process claims and not product claims” (para 75), and that “Section 3(i) does not make any distinction between in vivo or in vitro processes” (para 79). Of the subject invention it held that “The term ‘diagnosis’ itself would mean the process of obtaining a result as to whether any particular medical condition exists or not as also the stage thereof, if any” (para 93), and that “The Complete Specification read along with the final Claims leaves no manner of doubt that the subject invention is for a process of diagnosing and determining lung cancer” (para 96). “Insofar as opinion of the Patent Office on inventive step or Section 59 of the Act is concerned, the same is not being gone into” (para 103). “In view of the above discussion, the appeal of the Appellants against the refusal of grant of subject patent application fails and is liable to be dismissed.” (para 104)

What the court decided

1. Guidance from other jurisdictions. “Exclusions such as those contained in Section 3(i) of the Act also exist in other jurisdictions and before interpreting the scope of Section 3(i) of the Act and exclusions thereof, it would be useful to analyse the legal position in other jurisdictions.” (para 53) Of the observations of the Enlarged Board of Appeal in Case Number G0001/07, the Court held: “It is clear from the above observations, that the exclusion from patentability should be interpreted narrowly to limit its application to the purpose for which it was incorporated i.e., to ensure that medical professionals are not hindered by concerns of patent infringement in the performance of core clinical tasks that require professional medical expertise and carry health risks.” (paras 53, 56–57)
2. The evolved definition of invention. “The exclusions from patentability under Section 3(i) of the Act, therefore, was initially inserted at a time when method of manufacture was a necessary pre-condition for grant of a patent under Section 5 of the Act. However, when the exclusion in Section 3(i) was amended, the method of manufacture requirement was no longer in existence. The definition of invention has itself changed over the years and the exclusion, in the opinion of this Court, has to, therefore, be interpreted in the context of the evolved definition of invention.” (para 70) “The exclusion of methods/processes under Section 3(i) of the Act has to be, therefore, construed along with Section 2(1)(j) and 2(1)(ja) which define ‘invention’ and ‘inventive step’, respectively. The intention behind the provision has to be deciphered, contextually and in line with the present statutory provisions.” (paras 70–71)
3. The purpose of the exclusion. “All processes and methods for diagnostic purposes or are therapeutic in nature, which are used by medical practitioners or professionals, and are easily passed on to their peers and colleagues are not patented. This would ensure that no one individual or corporation is able to monopolize the implementation of these processes and methods or prevent the use thereof. ... Such methods or processes which form the core of medical practitioners’ activities i.e., the activities for which they are specifically trained and assume express responsibility/liability, if allowed to be patented, could hinder the use of the same by medical practitioners. It could also impede such medical professionals from rendering their patients free of disease or provide them with required medical attention and care.” (para 72) “In the opinion of this Court, 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. Accordingly, a nuanced interpretation is warranted, one that excludes only those methods which directly implicate professional judgment and involve invasive or high-risk procedures, while allowing for the patenting of ancillary tools, devices, and non-invasive methods, especially those practiced in vitro or outside the human/animal body. Such an approach upholds the delicate balance between incentivising innovation in health related technology and preserving unhindered access to performing essential medical procedures.” (paras 72–73)
4. Purpose, context and nature of intervention. “Accordingly, the manner in which processes which involve physical intervention in the patient’s body, must be performed by trained medical professionals, fall within the scope of the exclusion, whereas novel methods for performing cosmetic procedures such as a hair removal technique may not. For example, a method or process used by a nurse or a doctor for measuring blood pressure would not be patentable but a novel product for measuring blood pressure would be patentable. The former would impede medical professionals, while the latter may spring innovation. This is notwithstanding the fact that both may involve invasive or non-invasive techniques. The distinction lies in the purpose, context, and nature of the intervention, whether it pertains to core medical activity requiring professional judgment and carrying inherent risk, or whether it constitutes a low-risk, routine procedure commonly performed in non-medical, commercial settings. This distinction reflects a consistent principle of patent law, also applicable for interpretation of Section 3(i) of the Act, 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. Accordingly, in interpreting Section 3(i) of the Act, which uses similar language as Art. 53(c) of the EPC, the same rationale ought to guide the analysis, i.e., to preserve the freedom of medical practitioners in clinical settings, while still enabling the protection of technical solutions, tools, or methods that are either in vitro or non-clinical in nature.” (para 74)
5. Process claims and product claims. “While, safeguarding this critical aspect, the intention behind enacting Section 3(i) of the Act is to ensure that the practice of medicine and various critical steps involved therein are not hindered in any manner by the grant of patents. It is not meant to disregard or discourage innovation in the field of medicine. 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. Thus, tools and products irrespective of whether they are in vivo or in vitro are entitled to grant of patent even if they can be used in the process of performing surgery, diagnosis or therapy, provided they satisfy the conditions under Section 2(1)(j) and 2(1)(ja) of the Act. However, each product claim would have to be analysed on a case to case basis since, laying down an objective test could be quite challenging as a close scrutiny would be required to decipher as to what is patentable and what is not.” (para 75)
6. Obiter. Artificial intelligence in diagnosis. “Such a qualification of adding medical practitioners in the exclusion, could pose challenges once artificial intelligence is used in diagnosis or treatment. ... the intervention of a medical practitioner would be required for the diagnosis or prescribing of treatment. ... The AI tools would merely assist in diagnosis or therapy and cannot substitute the judgment or decision of the medical practitioner as to the conclusion of the medical condition or the treatment to be given.” (para 77)
7. The salient points on section 3(i). “Thus, in view of the above discussion, the salient points for interpretation of Section 3(i) of the Act may be summarised as under: (i) 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.” “(ii) A perusal of the various terminologies used in Section 3(i) of the Act shows that the exclusions are meant for processes which are employed by medical practitioners, para-medical personnel, nurses, etc. The interpretation of key terms in Section 3(i) of the Act in the context of other provisions of the Act would be as under: (a) ‘Medicinal process’ would mean processes which are used for administration of medicines such as a process for oral administration, a process for administration through intravenous therapy, a process for administration of medicine through topical, transdermal or subcutaneous routes or a process through insertion of the medicine, etc. but would not include medicinal products, medicines, medical devices, or even patentable product by process inventions. (b) ‘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. For example, the manner of conducting a colonoscopy or heart transplant surgeries, including the method for sutures or the manner of creating an incision, etc., which are commonly used by surgeons would not be patentable. However, a novel product such as an innovative scalpel used in conducting the surgery would be patentable.” “(c) ‘Curative process’ - this terminology is quite ambiguous and vague, considering the various other terms and expressions used in Section 3(i) of the Act. Curative means ’treatments and therapies aimed at eliminating a disease, injury, or illness to restore a person’s health to its prior state’. Thus, 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. (d) ‘Prophylactic process’ means a process for prevention of disease, for example, a process of administering a vaccine or a process of conducting cancer screening, blood test etc., would not be patentable. However, preventive tools, preventive products or preventive mechanisms which qualify the test of patentability would not be excluded.” “(e) ‘Diagnostic process’ - The manner in which diagnosis is performed would not be patentable, for example, the manner of checking blood pressure using different tools, the manner of doing a swab test, the process of checking glucose levels, etc., would not be patentable. However, diagnostic products, diagnostic tools, diagnostic devices are patentable so long as they satisfy the test of patentability and they do not unfairly monopolize processes of diagnosis which are to be generally used by medical practitioners, nurses etc. It is also clear that Section 3(i) does not make any distinction between in vivo or in vitro processes.” “(iii) Tools which could be used for the purpose of diagnosis would also not be covered by the exclusion and would be patentable. However, if tools only consist of software-based tools, which utilize data for the purpose of diagnosis, they would have to be examined under Section 3(k) of the Act for further technical effect and for satisfying the conditions for patentability. In addition, it would have to be checked if these tools or processes by themselves give results which are capable of clear interpretation as to the existence or non-existence of a medical condition.” “(iv) The phrase ’to render them free of disease or to increase their economic value’ qualifies only treatment of animals and not of human beings;” “(v) Mere identification of the regimen for the use of certain medicines in a particular manner or frequency or form would be excluded from patentability.” “(vi) 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)
8. The meaning of diagnosis. Of the appellants’ submission “that the subject invention does not give conclusive discovery or identification of the exact cause of illness or problem and therefore, it is not diagnostic in nature” (para 92), the Court held: “In the opinion of this Court, this submission is completely meritless as identification of the exact illness, problem or cause would merely be one of the elements of diagnosis. The term ‘diagnosis’ itself would mean the process of obtaining a result as to whether any particular medical condition exists or not as also the stage thereof, if any. It cannot be accepted that only those methods which finally confirm the presence of a particular illness, disease or medical condition would be a diagnostic method. In view of the discussion hereinabove on interpretation of diagnostic methods, where the result of performing a method would initially confirm the absence of a particular illness, disease, genetic defect, medical condition etc., or negation of the same in an individual, the said method would also fall within the scope of diagnosis - irrespective of the said method being performed as an in vivo or invitro test.” (paras 92–93)
9. The cause of illness. “Furthermore, the argument that a diagnostic method would require identification of a particular cause of the illness or medical condition is also untenable. For example, in the case of cancer, it is publicly known that there could be numerous factors which may cause cancer, especially lung cancer, such as pollution, smoking, etc., however, the diagnosis itself is not meant to identify the cause for cancer, but the existence or absence of the carcinoma i.e., cancer. Thus, the test that is professed by the Appellant that diagnosis is meant to identify the exact cause of illness or a problem is not an acceptable test.” (para 94)
10. The specification read with the claims. “In respect of the subject invention, the complete specification in the present case, leaves, no manner of doubt in the language which is used that upon conducting a test through an amplification method using bespoke PCR” (“Polymerase Chain Reaction”) “, the presence of cancerous cell is sought to be established/ identified.” (para 95) “The detailed description of the invention also makes it abundantly clear that the intention of the subject invention is to obtain a definitive result. The various embodiments in the invention are intended to determine whether it is lung cancer or whether it is squamous cell carcinoma or adenocarcinoma and what is the stage of carcinoma. The Complete Specification read along with the final Claims leaves no manner of doubt that the subject invention is for a process of diagnosing and determining lung cancer i.e., squamous cell carcinoma, along with the stage at which the same is present in an individual. The subject invention is clearly hit by Section 3(i) of the Act, especially considering the fact that the complete specification even confirms that in some embodiments there is a definitive result being obtained as well.” (paras 95–96)
11. Further tests before treatment. “This Court is conscious of the fact that insofar as cancer is concerned, the nature of the disease may require further test to be performed on the patient before the treatment begins, however, this by itself cannot, in any manner, neutralise or dilute the purpose of the subject invention i.e.,that the process is meant to detect lung cancer.” (para 97)
12. Skilful drafting of claims. “It would also be necessary to observe that one cause of concern for this Court is that various claims which have been filed from time to time have tried to create a veil so that the claims can escape the objection of Section 3(i). However, as held in Novartis AG v. Union of India, (2013) 6 SCC 1 skilful drafting would not help in such cases.” The Court reproduced the observation of the Supreme Court in Novartis v Union of India (2013): “We certainly do not wish the law of patent in this country to develop on lines where there may be a vast gap between the coverage and the disclosure under the patent; where the scope of the patent is determined not on the intrinsic worth of the invention but by the artful drafting of its claims by skilful lawyers” (para 98)
13. Grants in foreign jurisdictions. “This Court also notes that the subject invention may have been patented in some foreign jurisdictions, however, the statutory prohibition in India being what it is, the mere grant in foreign jurisdictions would not lead to grant of the patent in India.” (para 99)
14. Conclusion and disposition. “Thus, in view of the above discussion and considering the Complete Specification read with the final Claims clearly shows that the subject patent is for a process for diagnosis and detection of lung cancer. The statute as it stands, therefore, would not permit the grant of subject patent.” (para 100) “In view of the above discussion, the appeal of the Appellants against the refusal of grant of subject patent application fails and is liable to be dismissed.” (para 104) “Accordingly, the present appeal along with pending applications if any is disposed of in the above terms.” (paras 100, 104, 106)

What the court did not decide

The third issue was whether “Claims 5 to 8 of the subject patent application would be impermissible in view of Section 59 of the Act” (para 52). The Patent Office’s report, reproduced by the Court, stated that “inventive step for amended claims 1-8 cannot be acknowledged u/s 2(1)(ja) of the Patents Act, 1970 (as amended)” and that “the claims 5-8 drawing support once again from original PCT claims 41,42, 23,47 and 52 at the time of hearing written submission is not allowable under Section 59 of the Patents Act 1970” (para 102). The Court held: “Insofar as opinion of the Patent Office on inventive step or Section 59 of the Act is concerned, the same is not being gone into inasmuch as this Court is of the opinion that subject patent is hit by Section 3(i) of the Act.” (para 103) It also made it clear “that the question as to whether in order to enable innovation in the field of biotechnology, such an embargo should exist or not would fall in the realm of policy considerations, which is beyond the remit of this Court.” (para 101)

Subsequent treatment

• Followed — In Hirotsu Bio Science v Assistant Controller of Patents and Designs (2026) the Delhi High Court (Tejas Karia J) held that “the Paragraph No. 79 of Natera Inc. and Anr. (supra) clearly notes that the Section 3(i) of the Act does not make any distinction between in vivo or in vitro processes” (para 17), and that “The term ‘diagnostic process’ has been explained in Paragraph No. 79 of Natera Inc. and Anr. (supra), wherein the Court held that the manner in which the diagnosis is performed would not be patentable” (para 31).
• Followed — In Geron v Assistant Controller of Patents and Designs (2026) the Delhi High Court (Manmeet Pritam Singh Arora J) recorded that “A Co-ordinate Bench of this Court has recently clarified the exclusion of diagnostic method under Section 3(i) of the Patents Act in Natera Inc. & Anr. v. Assistant Controller of Patents and Designs (supra)” (para 21), reproduced para 79 of this judgment, and, citing it, held that “Granting a patent to this subject matter will result in monopolising a medical practitioner’s medical decision-making practice of measuring telomere length” and that “Such a monopolisation is in violation of Section 3(i) of the Patents Act” (para 32).

No further appeal traced as of 10 October 2026.