Every patent application claiming a composition of known ingredients must climb over the synergy cliff to qualify for the grant of a patent under Section 3(e) of the Patents Act, 1970. The Delhi High Court dismissed the appeal in Crystal Crops vs Assistant Controller of Patents [C.A.(COMM.IPD-PAT) 19/2023], dated February 28, 2026, and ruled that a real technical advance or a credible synergistic effect is essential for the grant of the claimed composition of known ingredients. In an ongoing dispute over the patent eligibility of an herbicidal composition for the control of major unwanted vegetation in a wide variety of agricultural crops. The claim for synergistic herbicidal composition read as “A herbicidal composition comprising synergistically effective amount of two active ingredients, wherein the first active ingredient is Halosulfuron methyl in an amount ranging from 10-15%wt and the second active ingredient is Metribuzin in an amount ranging from 50-60%wt”.
The application by Crystal Crop faced twin pre-grant oppositions under Section 25(1) of the Patents Act, 1970, viz. Haryana Pesticides Manufacturers’ Association (Opposition filed in 2017) and Dr. Meera Sharma (Opposition filed in 2022). The second opponent also sought the leave of the Court to file an additional document. The Court applied the F-Hoffmann 5-step test to check whether the respondent had applied these steps taking decision on the ground of lack on inventive step under Section 2(1)(ja) of the Act and found that the respondent Controller had discussed the inventive concept embodied in the subject patent of the present invention and complied with the 3rd step that pertains to common general knowledge in the art at the priority date when he discussed cited prior arts in detail.
The respondent Controller then compared the cited documents with the present invention and arrived at the assessed conclusion. According to the Court, the impugned order was well-reasoned and did not contain any infirmities. The Appeal Court upheld the decision of the Controller for the refusal of a patent on the grounds of lack of inventive step and not patentable under Section 3(e) for lack of evidence to prove the synergy between the known ingredients used in the claimed invention.
Appellant’s Case
The appellant objected to the second opponent’s filing of an additional document on the ground that it was publicly available and should have been presented to the Controller during the pre-grant opposition proceedings. The appellant argued that allowing them at the appellate stage would enable the opponents to unfairly fill gaps in their case. The appellant submitted introduction of new evidence at the appeal stage should not be considered. Moreover, Respondent No. 2 did not show how admission of the additional documents was necessary to pronounce a satisfactory judgment. The appellant maintained that the claimed composition involved a synergistic herbicidal composition of halosulfuron-methyl and metribuzin in specific proportions that produced an effect greater than the additive effect of the individual components. The appellant submitted that the experimental data in the specification clearly demonstrate that the composition achieved improved weed control at lower dosages.
Respondent Controller’s Reply
The respondent Controller maintained that they considered all the written arguments and submissions of the contesting parties and concluded that the application should be refused on the grounds of lack of inventive step, and that the claimed subject matter falls within the excluded patentable invention under Section 3(e). The respondent Controller submitted that the subject application was required to show that it involves a technical advance as compared to the existing knowledge, or has economic significance, or both, as compared to the prior art, namely D1, D2 and D5.
According to the respondent Controller, the appellant was required to demonstrate technical advancement by producing experimental data, which was not done in the case. Respondent 1 relied on the Court’s ruling in Astrazeneca AB and Ors. vs Intas Pharmaceuticals Limited and Ors., 2020 (84) PTC 326 (Del). They submitted that the patent application was refused under Section 3(e) on the ground of lack of evidence of synergy between the known ingredients used in the claimed invention.
Submissions by Respondent 2 (2nd Pre-Grant Opponent)
Respondent No. 2 submitted that the appellant had to put data and compare it with the synergistic data, and no such data was provided by the appellant. Therefore, as per Respondent No. 2, the synergistic effect was not proved. Respondent No. 2 further concluded that the appellant did not furnish any experimental results/comparative synergy data which demonstrate the technical enhancement/unexpected efficacy over the cited documents.
Court’s Findings and Analysis
On Admissibility of Additional Documents
The Court noted that, as per Intellectual Property Division Rules, under Rule 6(iv) and (v), the additional documents can be allowed with the leave of the Court if the party who submits the additional documents have specified the details and relevance of the additional documents. The Court observed that, in the present case, the details were provided by Respondent No. 2 in a table, which clearly establishes the relevance of these documents, and that these additional documents are highly pertinent to resolving the dispute between the Parties. The Court ruled that these documents should be admitted and form part of the records of this appeal.
On Technical Advance and Inventive Step
To find the technical advance as envisaged under Section 2(1)(ja), the Court applied the Hoffman test to assess the presence of inventive step. The Court compared the cited document with the claimed invention and found that the cited document discloses all the claimed ingredients of the composition. The Court noted that a simple tweaking of known ingredients was not an innovation unless it demonstrated a real technical advance.
On Showing Credible Presence of Synergistic Effect
According to the Court, in the present case, the appellant failed to provide data to show the synergistic effect of the claimed composition. According to the Court, the contention of the appellant that claimed composition achieved improved weed control at lower dosages is not convincing to establish the synergistic effect required under Section 3(e). The Court noted that simply increasing the doses of known ingredients was not innovation unless it demonstrated a real and credible synergistic effect.
Court’s Decision
The Court dismissed the appeal, ruling that there was no infirmity in the impugned order. The Court upheld the refusal of Crystal Crop’s patent application for a herbicidal composition combining halosulfuron-methyl and metribuzin.
Conclusion
The ruling in this appeal hinged on whether the claimed subject matter is a mere admixture and possesses a technical advance over the existing knowledge. The appellant failed to prove the technical advance over the existing knowledge and failed to pass the synergy test required under Section 3(e). The Court found that the Crystal Crop has simply tweaked the known ingredients by increasing their doses, which would not qualify as an invention under Section 2(1)(ja) unless the applicant can show a real technical advance. The Court ruled that the claimed composition failed to demonstrate a real or credible synergistic effect necessary to qualify for patent protection under Section 3(e). This case highlights that claims to a composition of known ingredients should provide credible proof of a synergistic effect to avoid the cliff of non-patentable mere admixture under Section 3(e).