Section 3(d) of the Indian Patents Act, 1970 holds a unique position within India’s patent law framework, particularly in relation to life sciences. It imposes additional scrutiny on patent applications concerning processes in this field. According to Section 3(d), patents cannot be granted for the mere use of a known process unless it results in a new product or involves at least one new reactant.
In a recent judgment on March 10, 2023, the Delhi High Court addressed the matter of Tapas Chatterjee vs Assistant Controller of Patents and Designs and Anr  where the Court upheld the refusal order issued by the Controller, affirming that a process can be deemed known if it merely combines known processes from prior art. Consequently, a patent can only be granted for a known process if it leads to a new product or incorporates at least one new reactant.
Facts of the Case
Tapas Chatterjee, hereinafter referred to as the “Appellant,” filed an Appeal challenging the Assistant Controller of Patents, hereinafter referred to as the “Respondent’s refusal to grant a patent for application no. 201911036748. The refusal was based on the grounds of non-patentability under Section 3(d) and lack of inventive step under Section 2(1)(ja) of the Indian Patents Act.
Relevant Law and/or Rule
- Section 2(1)(j): “invention” means a new product or process involving an inventive step and capable of industrial application.
- Section 2(1)(ja): “inventive step” means a feature of an invention that involves technical advance as compared to the existing knowledge or having economic significance or both and that makes the invention not obvious to a person skilled in the art.
- Section 3: What are not inventions.—The following are not inventions within the meaning of this Act,—
(d) the mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance or the mere discovery of any new property or new use for a known substance or of the mere use of a known process, machine or apparatus unless such known process results in a new product or employs at least one new reactant.
Explanation.—For the purposes of this clause, salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substance shall be considered to be the same substance, unless they differ significantly in properties with regard to efficacy
The Appellant contended that the Respondent failed to identify a reference point process that could be considered a “known” or “old process” to reject the application under Section 3(d). The Appellant relied on the judgment in DS Biopharma v. Controller of Patents and Designs, 2022  to support this argument.
Additionally, the Appellant argued that as the invention was acknowledged as novel by the Respondent, the provisions of Section 3(d) should not apply. They stated, “As the process is not hit by the bar of Section 3(d) of the Act, the need to involve a new reactant or ingredient does not arise.”
Furthermore, the Appellant asserted that their process involved a new step of “thermal decomposition” with repeated fractionation, resulting in the production of a significant amount of pure commercially usable potassium sulfate and recyclable water. They contended that this novel and inventive process followed a distinct sequence of steps. Even if some ingredients or steps of the process were known, the combination of steps remained patentable under Section 3(d). The Appellant drew support for this argument from an extract from the Commentary on Patent Law by P. Narayanan (4th Edition).
The Appellant also emphasized that the Respondent must identify prior art demonstrating how a person skilled in the art could arrive at the subject invention without referring to it directly. They argued that using the subject invention as a blueprint to map prior art onto it would amount to a hindsight analysis. In this context, the Appellant cited the judgment in Avery Dennison Corporation v. Controller of Patents and Designs (2023) .
The Respondent, in relation to Section 3(d), argued that the subject application’s process did not involve any new reactant nor result in the creation of a new product.
Regarding Section 2(1)(ja), the Respondent contended that the subject invention did not differ from the teachings of D2. They stated, “Merely because the appellant uses the process of thermal decomposition to break down one compound into two or more new compounds would not result in any technical advancement when compared with the cited prior art references. The claimed process does not yield a new product, and the end product in all the cited prior art documents D1 – D4 is the same, i.e., Potassium Sulphate.”
The Respondent also argued that the Appellant failed to provide any experimental data, examples, or supporting evidence to substantiate the economic advantages of the claimed process concerning potassium sulfate recovery.
Decision of the Court
The Court concluded that the claimed process fell within the scope of Section 3(d) since it constituted a mere combination of known processes disclosed in the prior art documents D1 and D2. The Court clarified that the term “known process” in Section 3(d) also encompasses multiple known processes, as evident in the present case. According to Section 3(d), a patent for a known process can only be granted if it results in a new product or involves at least one new reactant.
Furthermore, the Court highlighted a significant distinction between the “discovery of a new form of a known substance” and the “mere use of a known process.” In the case of the former, a patent can only be granted if the new form enhances the known efficacy of the substance. However, there is no such provision for the enhancement of known efficacy in relation to known processes. Therefore, the scope for patentability of processes is narrower than that of substances.
Upon reviewing the prior art documents D1 and D2, it became apparent that the processes used in the subject invention were nothing more than a combination of known processes. The Court agreed with the Respondents that the subject application did not introduce any new reactants into these processes, nor did the final process result in the creation of a new product. The only distinguishing factor between the subject patent and the cited prior art was the Appellant’s adoption of a zero liquid discharge process, while the prior arts described processes that discharged effluents. However, the Court concluded that these differences were insufficient to overcome the objection raised by the Respondents under Section 3(d) of the Act.
The Court further discussed the five-step test to determine inventive step under Section 2(1)(ja), as established in F. Hoffmann-La Roche Ltd. and Ors. v. Cipla Ltd., 2016 . Specifically, the Court emphasized steps 4 and 5, which involve identifying differences between the cited matter and the alleged invention and determining whether those differences would have been obvious to a person skilled in the art without a hindsight approach.
Upon comparing the claims of the subject application with those of D1 and D2, the Court held that a person skilled in the art, by combining the teachings of the cited prior art, would have arrived at the subject invention without any inventive step.
Analysis and Conclusion
The judgment delivered by the Delhi High Court in the case of “Tapas Chatterjee vs Assistant Controller of Patents and Designs and Anr.” sheds light on the interpretation and application of Section 3(d) of the Indian Patents Act in relation to known processes. The Court’s decision reaffirms the strict requirements for patentability and emphasizes the need for novelty and inventive step in order to grant a patent.
In this case, the Court carefully analyzed the provisions of Section 3(d) and observed that a patent for a known process can only be granted if it results in a new product or involves at least one new reactant. Mere combinations of known processes, without any additional elements leading to novelty or inventive step, do not meet the requirements for patentability. The Court’s decision highlights the importance of the “new product” or “new reactant” requirement in determining the patentability of known processes. It clarifies that the scope for patentability of processes is narrower than that of substances. While the discovery of a new form of a known substance requires enhancement of its known efficacy to qualify for a patent, no such provision exists for known processes.
Overall, this judgment serves as a reminder to patent applicants and practitioners to thoroughly evaluate the novelty and inventive step of their claims, particularly when dealing with known processes. It emphasizes the need to meet the strict requirements of the Indian Patents Act and reinforces the principle that patents should be granted for genuine advancements in technology, rather than mere combinations of existing knowledge.
In conclusion, the Delhi High Court’s decision provides valuable guidance on the interpretation of Section 3(d) and sets a precedent for assessing the patentability of known processes. It underscores the significance of meeting the statutory requirements, including novelty and inventive step, and serves as a reminder to stakeholders in the field of life sciences to carefully assess their claims before seeking patent protection. By upholding the strict standards for patentability, this judgment promotes innovation and ensures that patents are granted for genuine technological advancements that contribute to the progress of society.
 C.A.(COMM.IPD-PAT) 18/2022 & I.A.3580/2022
 C.A. (COMM.IPD-PAT) 6/2021 & I.A. 12828/2021
 C.A. (COMM.IPD-PAT) 29/2021
 2016(65) PTC 1 (Del)