The Delhi High Court has dismissed the application for an interim injunction filed by FMC Corporation and others against Natco Pharma Limited in a patent infringement suit over an agrochemical intermediate. The court’s decision hinged on the finding that Natco Pharma had raised a strong, credible challenge to the validity of the patent.
The Dispute FMC Corporation, the patentee, sought an injunction to restrain Natco Pharma from manufacturing and selling its product ‘Cyantraniliprole 10.26% OD’. The plaintiffs alleged that Natco Pharma’s product infringed Claim 12 of the suit patent (IN 298645), which covers an intermediate compound used in the manufacturing process, with the patent set to expire in December 2025. Natco Pharma admitted to using the intermediate but challenged the patent’s validity, contending it was anticipated by prior art.
Court’s Key Findings Justice Mini Pushkarna, in dismissing the application, reinforced established legal principles regarding patent litigation:
- No Guarantee of Validity: The court noted that the mere grant of a patent does not guarantee its validity, nor does it automatically entitle the patentee to an injunction. There is no presumption of validity under Section 13(4) and Section 64 of the Patents Act.
- Credible Challenge: An injunction must be denied if the defendant is able to show that the patent is “vulnerable” by raising a serious and substantial question as to its invalidity. The court observed that Natco’s challenge, which included citing prior international publications, was a strong and credible one.
- Compensable Damages: The court also found that the balance of convenience was not in favour of granting the injunction, as any potential damages to the plaintiffs—if they succeed at trial—appeared to be compensable, especially since FMC seeks to monetize the invention through import and licensing.
Natco Pharma, having already commenced commercial production and marketing, was directed to continue placing on record the details, quantum, and value of the product manufactured and sold. The court clarified that the observations are only prima facie for the purpose of the interim relief and will not influence the final decision on the merits of the case, which will proceed to trial.
FMC CORPORATION & ORS. vs. NATCO PHARMA LIMITED, 17-11-2025