An unwelcome bend in jurisprudence for patent composition claims?

In order to meet patentability criteria, an invention must be novel, inventive and industrially applicable. Roadblocks to patentability can arise under Section 3 of the Patents Act, which defines non-patentable subject matter. However, a recent judgment from the Delhi High Court, in Best Agrolife Limited v Deputy Controller of Patents & Anr (WP ©-IPD 11/2022 & CM 32/2022, 54/2022, 55/2022), has created additional confusion in this tricky area.

Statutory provisions

Section 3(d) bars the patentability of a:

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.”

Section 3(e) bars the patentability of a substance obtained by a mere admixture resulting only in the aggregation of the properties of the components thereof, or a process for producing such substance.

Both these provisions are unique to India – they aim to prevent patent ever-greening and restrict the patentability of secondary patents. In India, a majority of secondary patents are directed to formulations, compositions and combinations – many of which fall under the purview of Sections 3(d) and (e). To rebut a Section 3(d) objection, an applicant must submit comparative efficacy data, while for a Section 3(e) objection it must demonstrate synergism.

While addressing the question of whether Section 3(d) is applicable to inventions relating to compositions/formulations/combinations in Ajanta Pharma Ltd v Allergan Inc (ORA/20/2011/PT/KOL, the Intellectual Property Appellate Board (IPAB) held that the combination mentioned in the explanation  to Section 3(d) can only refer to two or more of the derivatives mentioned in the explanation, or a combination of one or more of the derivatives with the known substance that may result in a significant difference with regard to the efficacy. However, Section 3(d) was found not applicable, if the components of the composition were not derivatives of each other. This interpretation also finds mention in the 2014 IP Office Guidelines for Examination of Patent Applications in the Field of Pharmaceuticals’. However, the Delhi High Court’s decision in Best Agrolife Limited v Deputy Controller of Patents has now posed a challenge to this position.

The Best Agro matter

Best Agro and some other parties filed pre-grant oppositions under Section 25(1) of the Patents Act, opposing the grant of a patent filed by GSP Crop Science on several grounds including lack of novelty under Section 25(1)(b) and non-patentability under Section 25(1)(f) read with Sections 3(d) and 3(e) of the act, as well as the scope of the amended claims. The controller, after hearing the parties, rejected the pre-grant oppositions and granted the patent as IN 394568. Best Agro challenged this order before the Delhi High Court.

The main ground of the challenge was that the controller had issued a non-speaking order, which clearly violated of the principles of natural justice. Best Agro argued that there was no finding in the controller’s decision with regard to its arguments made with respect to Section 3(d). There was a failure to compare the data of the formulations as disclosed in the prior arts cited in support of Section 3(d) of the act, alongside a failure to consider whether the composition, as claimed, would cross the threshold of Section 3(d), especially when prior arts cited by the petitioner disclosed suspo-emulsion formulations of pyriproxyfen and diafenthiuron. 

Best Agro argued that an inquiry envisaged under Section 3(d) is independent of an inquiry under Section 3(e). Section 3(d) deals with the assessment of the enhanced efficacy of a claimed composition in comparison to the efficacy of a known substance and not merely a comparison of efficacy with the individual components of the composition. Section 3(e), on the other hand, concerns the assessment of synergistic effect of claimed composition over individual properties of each component of the composition. The respondent urged that the objection under Section 3(d) was in effect considered and rejected, although not separately mentioned in the impugned order, since the finding under Section 3(e) covers the finding under Section 3(d). It was also contended that relevant parameters of bio-efficacy, toxicity and stability relate to Section 3(d) and their consideration under Section 3(e) covers adjudication under Section 3(d).


After hearing both parties, the court concluded that principles of natural justice had been denied to the petitioner on many grounds. The court alluded to the Indian Supreme Court’s decision in Novartis AG v Union of India, namely that the requirement under Section 3(d) cannot be underestimated. The court held that Section 3(d) sets up a second tier of qualifying standards in chemical substances/pharmaceutical products to encourage genuine inventions, at the same time keeping a check on ever greening. It found merit in the contention of the petitioner that the patent applicant had claimed a suspo-emulsion of admixture/combination of diafenthiuron and pyriproxyfen and, therefore, the applicant would have to pass the test under both Sections 3(d) and (e), albeit in different aspects by showing enhanced efficacy over the known combination of a suspo-emulsion qua Section 3(d) and synergistic effect over the mere additive effect of individual components of suspo-emulsion composition. The court also found prima facie merit in the contention of the petitioner that synergistic effect can be demonstrated by a combined effect of increased bio-efficacy and stability of the admixture beyond the sum of their individual effects. However, if bio-efficacy/stability is to be tested in respect of Section 3(d), the test would be bio-efficacy/stability of the form, that is, suspo-emulsion in this case and not the admixture, over and above the closest prior art brought forth by the opposer, which is the known substance as a comparator. It deferred to the petitioner’s contention that the test for Section 3(d) is for enhanced efficacy, while that for Section 3(e) is for synergistic effect and both operate in two different fields. The matter has been remanded to the Indian Patent Office (IPO) to consider the matter afresh and render a decision within eight weeks.

It is likely that the court’s observations will embolden the IPO to raise Section 3(d) objections and insist upon efficacy data for composition claims, which is normally not the case in view of the IPAB’s Ajanta order. While the procedural irregularities and denial of principles of natural justice in the present case is a fit case for the court to interfere in, the patent fraternity may not be wrong in being a little wary of the avalanche of objections that may be triggered for composition claims with regard to Section 3(d).  

Meanwhile, a full-fledged reasoned order from the controller is awaited.

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