The ongoing patent litigation between FMC and Natco involving the Cyantraniliprole and Chlorantraniliprole patent families since 2022 took a new turn when the Delhi High Court denied FMC’s quia timet Injunction plea against Natco Pharma relating to FMC’s patent IN 298645 on Cyantraniliprole 10.26% OD (Oil Dispersion), useful as an insecticidal composition. FMC alleged that the Natco product (Cyantraniliprole 10.26% OD) infringed the patented Compound of Formula 3 as claimed in Claim 12 of IN’ 645 patent. FMC pleaded for a grant of a quia timet injunction to restrain Natco from using the Cyantraniliprole intermediate.
The suit patent claims a process for the preparation of Cyantraniliprole in Claims 1 to 11, and Claim 12 relates to Cyantraniliprole 3, which is an intermediate used in the said process. FMC holds multiple patents on Cyantraniliprole, Chlorantraniliprole, and their compositions. Both parties have been engaged in continuous patent litigation involving this patent family since 2022. The patents in the dispute are IN 277358, IN 201307, IN 213332, and IN 298645.
Natco initially filed a declaratory suit seeking a declaration of non-infringement of Claims 1-11 of IN’645 relating to the manufacture of Chlorantraniliprole. FMC responded with an infringement action, in which the interim injunction was refused. Natco later filed another declaratory suit seeking non-infringement of FMC’s patent IN 277358 concerning Cyantraniliprole 10.26% OD. Subsequently, Natco also filed a revocation petition challenging Claim 12 of IN’645.
FMC submitted that interim relief was appropriate given the imminent expiry of the patent and Natco’s launch during proceedings, and the narrow scope of relief sought (limited to the intermediate). In April 2025, Natco received the required regulatory approvals and commenced commercial manufacture of Cyantraniliprole 10.26% OD. Meanwhile, FMC instituted three additional suits in Chandigarh alleging infringement of Claim 12, which were later transferred to the Delhi High Court.
Thus, the present suit was filed by the FMC seeking relief against Natco’s use of the intermediate compound in question in the manufacturing of the impugned product, as the intermediate compound is protected under Claim 12 of the suit patent. Therefore, the application in question before the Court sought an interim injunction against the Natco usage of the intermediate compound in question, i.e., 2-amino-5-cyano-N, 3-dimethylbenzamide, which is protected by Claim 12 of the suit patent.
List of Related Court Proceedings
The present suit has a history, beginning with FMC filing a suit in 2019 [FMC Corporation & Anr. vs Natco Pharma Limited C.S. (COMM) 611/2019], seeking to restrain Natco from infringing another set of FMC’s patents of the same family IN 201307 and IN 213332. On May 6, 2022, Natco filed a declaratory suit before the same Court via Natco Pharma Ltd. vs FMC Agro Singapore Pte. Ltd. & Ors [C.S. (COMM) 295/2022], under Section 105 of the Patents Act, 1970, seeking a prayer for declaration of non-infringement in respect of Claims 1 to 11 of the IN’645 relating to manufacture of another product ‘Chlorantraniliprole’. On May 20, 2022, FMC filed a suit for infringement of IN’645 [FMC Corporation & Others vs Natco Pharma Limited C.S. (COMM) 349/2022], seeking an injunction against Natco with respect to infringement of Claims 1, 5 to 8, and 11 of the suit patents.
On September 19, 2022, the Court dismissed FMC’s application for an interim injunction against Natco, after which, FMC filed an appeal [FAO (OS)(COMM) 301/2022] against the judgment. On December 5, 2022, the Division Bench of the Delhi High Court dismissed the appeal and affirmed the judgment dated September 19, 2022.
In October 2023, Natco filed another suit for declaration, [Natco Pharma Limited vs FMC Agro Singapore Pte. Ltd. & Ors. C.S. (COMM) 787/2023], seeking a declaration of non-infringement in relation to another FMC patent, IN 277358 (“IN’358”), regarding the impugned product, Cyantraniliprole 10.26% OD.
Natco filed a revocation petition [C.O. (COMM-IPD-PAT) 7/2023], and in response, FMC filed three suits, viz. C.S. 11/2023, C.S. 2/2024 and C.S. 3/2024, against Natco before the District Court (Commercial), Chandigarh, seeking to restrain the defendant from infringing Claim 12 of the suit patent IN’645 in relation to Natco’s impugned products, namely ‘NATGEN‟, ‘NATLIGO‟ and ‘NATVOL‟. The suits were transferred to the Delhi High Court by the Supreme Court by way of an order dated April 9, 2024, in Transfer Petition (Civil) Nos. 504, 488, and 513 of 2024 [C.S. (COMM) 410/2024, 409/2024, and 408/2024, respectively], which are currently pending. IN‟645 was set to expire on December 6, 2025.
FMC Corporation’s Case
FMC sought a quia timet action under Section 48 read with Section 108 of the Patents Act, 1970 seeking permanent injunction, restraining the Natco from manufacturing/preparing the product, Cyantraniliprole 10.26% OD (“infringing/impugned product”) and/or other admixture, combination, formulation products containing Cyantraniliprole using the Compound of Formula 3 as claimed in Claim 12 as a specific intermediate. FMC argued that Natco had acknowledged using the intermediate compound protected by Claim 12, thereby clearly establishing prima facie infringement of the suit patent.
FMC contended that IN’104 could not qualify as prior art because its amended claims were published on August 15, 2008, well after the priority date of IN’645 (December 7, 2004). FMC also argued that WO’226 did not disclose or enable the specific intermediate of Claim 12 and therefore could not anticipate the suit patent. FMC argued that Claim 12 of the suit patent was used to manufacture and launch a product of Cyantraniliprole, which was manufactured by Natco using the intermediates claimed in that claim.
Natco’s Counterargument
Natco argued that it had filed the revocation petition, C.O. (COMM.IPD-PAT) 7/2023, prior to the filing of the present suit by the plaintiffs. In the revocation application, they had raised a substantial, credible challenge to the validity of Claim 12 of the suit patent. Natco submitted that Claim 12 of IN’645 was invalid because the intermediate had already been claimed in FMC’s earlier patent IN’104, which carries a priority date of 22 January 2002. Therefore, as the defendant at the present prima facie stage demonstrated a credible challenge to the patent, the interim injunction should not be granted.
Natco contended that FMC has filed multiple proceedings before the Court with respect to the suit patent, and that the present suit was an abuse of the process of the Court. Natco submitted that FMC, despite having filed several litigations between the parties, had been unable to obtain any favourable orders from this Court, particularly when the defendant had already disclosed the use of the intermediate compound in question, i.e., 2-amino-5-cyano-N, 3-dimethylbenzamide, for the purpose of manufacturing Cyantraniliprole. Therefore, in view of the conduct of the plaintiffs in earlier proceedings, the plaintiffs were not entitled to any equitable/interim relief. Natco placed reliance on the Gillette Defence, arguing that if a defendant’s product or process is wholly within expired prior art, infringement does not arise.
Court’s Analysis and Findings
On Prior Claiming
The Court observed that, for the purposes of assessing prior claiming, the relevant date is the “date of priority”, and not the “date of publication”. The Court found that IN’104 is a divisional of IN’417; therefore, it automatically inherited the earlier priority date of 22 January 2002 and constituted valid prior art against Claim 12 of IN’645. The Court found that Formula 6 of Claim 1 in IN’104 prima facie covered the same intermediate compound represented as Formula 3 in Claim 12 of IN’645. The Court noted that IN’104 operated as a species claim, while Claim 12 functioned as its genus counterpart. This made the suit patent vulnerable to anticipation by prior claiming.
On Novelty
The Court found that WO’226 entered India as a national-phase application, and that patent IN’417 was granted. This application was subsequently divided to get patent IN’104. The Court found that WO’226 was published on July 31, 2003, a date earlier than the priority date of the suit patent. The Court also observed that the intermediate compound covered by Claim 12 of IN’645 appeared to be disclosed in WO’226, and prima facie Claim 12 was considered to be vulnerable to a validity challenge for anticipation.
On the Gillette Defence
The Court found Natco’s reliance on the Gillette Defence valid, observing that since the defendant’s product or process was wholly within expired prior art, infringement does not arise. The Court already found that the intermediate in IN’645 was prior claimed in IN’104, which already expired on January 16, 2023. The Court ruled that Natco was entitled to practice the compound. Natco’s plea of Gillette Defence was therefore prima facie tenable.
Balance of Convenience
The Court noted that, for the purpose of assessing an application for an injunction, it must consider the balance of convenience. In the present suit, the Court found that Natco had “cleared the way” by filing a revocation petition and disclosing its product in earlier proceedings before commencing commercial manufacture. With IN’645 due to expire in less than two months, any loss to FMC was compensable in damages, whereas an injunction would significantly prejudice Natco. The Court ruled that Natco has, at this interim stage, set out a credible challenge to the validity of Claim 12 of IN‟645, by showing that Claim 12 of IN‟645, the suit patent, is prima facie vulnerable to challenge. Therefore, an interim injunction could not be granted in favour of the FMC, and the balance of convenience favoured the defendant and against the plaintiffs.
Court’s Decision
The Court held that FMChad failed to make out a prima facie case for an interim injunction. Citing para 130, 131, and 135, Astrazeneca AB and Another vs Intas Pharmaceutical Ltd. 1[2020 SCC OnLine Del 2765] judgment, the Court ruled that “the patent is about to expire in less than two months and any injury that may be caused to the plaintiffs is purely monetary in nature and can be adequately compensated by damages. Therefore, considering the discussion as above with respect to the balance of convenience and irreparable harm as well as a prima facie case, this Court is not inclined to grant an injunction to the plaintiffs.” The Court directed Natco to place on record the details, quantum, and value of the product manufactured and sold. The Court dismissed the application for an injunction.
Conclusion
The patent wars relating to insecticide patents are heating up in India, with both the plaintiff and the defendants making efforts through multiple Court proceedings: the plaintiffs seeking a permanent injunction under Section 48 read with Section 108, and the defendants seeking a declaration of non-infringement under Section 105. The defendants also seek revocation of patents. With multiple proceedings relating to many patents of a family pending in the Courts, the Delhi High Court, in the present suit, looked into the plea of the FMC purely from the prospects of credible challenges raised by Natco, supported by the plea of Gillette Defence, and the balance of convenience, and denied the grant of injunction.
The Court noted that Natco, at this interim stage, prima facie set out a credible challenge to the validity of Claim 12 of IN‟645 by showing that the same was vulnerable to challenge. Thus, the defendant had set up a credible defence to the infringement action. Therefore, the balance of convenience lies in favour of the defendant and against the plaintiffs. We may wait for the outcome of this case after the trial, based on the merits, to determine the apparent effect of the enforcement of such patents in India.
Author: DPS Parmar
First Published by: Mondaq here