On Nov. 17, 2025, the High Court of Delhi delivered a judgment in FMC v. Natco, a case between FMC Corporation and others (“FMC group”) and Natco Pharma Limited (“Natco”). This case highlights critical aspects of Indian patent law, particularly concerning the assessment of prior art, the doctrine of species vs. genus patents, and the standards for interim injunctions in the context of agrochemical innovation and competition.

FMC v. Natco – Case Background and Parties Involved:

  • The plaintiffs: FMC Corporation (Delaware, USA), FMC IP Technology GmbH (Switzerland), and their Indian subsidiaries (FMC India Private Limited and Cheminova India Ltd)
  • The defendant: Natco Pharma Limited
  • Patent No.: IN298645 (IN645)
  • Patent Expiry Date: Dec 06, 2025
  • Patent Title: Method for Preparing N-Phenylpyrazole-1-Carboxamides

FMC v. Natco – Key Timeline and Procedural Posture:

  • The suit was filed by FMC as a quia timet action (a preventative measure to pre-empt infringement), seeking to prevent Natco from manufacturing, preparing, or commercializing products using the intermediate compound claimed in Claim 12, primarily to curtail marketing of Cyantraniliprole 10.26 % OD Oil Dispersion.
  • The application at issue sought an interim injunction a court order to immediately restrain Natco from the alleged infringing activities pending final trial.
  • The patent in question (IN645) was originally held by E.I. DuPont, later acquired by FMC, is set to expire on December 6, 2025.
  • Significant related litigations have taken place between the parties regarding different patent claims (notably involving IN104 and related patents).

FMC v. Natco – The Disputed Patent and Products:

  • IN645 covers 12 claims, with Claims 1–11 relating to process steps for making Cyantraniliprole, and Claim 12 specifically claiming an intermediate: 2-amino-5-cyano-N,3-dimethylbenzamide, among others.
  • The defendant’s product Cyantraniliprole 10.26 % OD allegedly uses this patented intermediate, which became the focus for the interim injunction requested by FMC.

FMC v. Natco – Arguments Presented:

Plaintiffs (FMC Group):

  • Asserted that the intermediary compound is protected under Claim 12, and use of this compound by Natco amounts to infringement.
  • Pointed out the compound’s exclusivity and the distinct inventive step of intermediates, separate from final products.
  • Argued that prior litigation concerned different claims; thus, this action is not barred by procedural rules.
  • Contended that invalidation of corresponding Chinese patents for Cyantraniliprole should not affect the Indian proceedings.
  • Maintained that the burden of proving patent invalidity lies on the defendant.

Defendant (Natco Pharma):

  • Acknowledged use of the intermediate compound but argued that the compound was already claimed and disclosed in an earlier patent (IN104), thus invalidating Claim 12 under Indian law.
  • Highlighted that the priority date (not the publication date) governs prior art determinations in India, making IN104 a valid prior claim.
  • Argued the genus vs. species doctrine: IN104 as a species patent specifically covers the compounds generically claimed in IN645.
  • Raised the Gillette Defence that all actions fall strictly within the prior art, so there is neither infringement nor a valid monopoly left to enforce.
  • Pointed out delays by FMC and public interest in limiting monopolies nearing expiration.

FMC v. Natco – Legal Issues and Court’s Analysis:

What Constitutes Prior Art?

  • The Court had to decide if IN104, a previous Indian patent by the same applicant, anticipated or disclosed the exact compound as the intermediate in question.
  • The distinction between filing / priority date and grant / publication date of patents was crucial. The court recognized the priority date (Jan 22, 2002) of IN104 as controlling, as per Section 64(1)(a) of the Patents Act.

Genus-Species Patent Doctrine:

  • IN645 was a broader, generic patent claim (genus), while IN104 contained specific, narrower claims (species).
  • Legal principle: A prior, specific species disclosure in a patent negates the novelty of later, broader genus claims that encompass it.
  • The court reviewed the chemical structure claims in both patents, determining that 2-amino-5-cyano-N,3-dimethylbenzamide, the compound utilized by Natco, was explicitly disclosed in IN104’s Claim 1 and mirrored in the broader genus of IN645.

Gillette Defence:

  • A doctrine derived from UK law, this principle permits a party to avoid liability for infringement if the alleged acts only replicate prior art.
  • The Court held that since Natco’s process falls squarely within the scope of IN104 (already in the public domain, patent expired in 2023), Natco’s activities are non-infringing, reinforcing the Gillette Defence.

Standards for Granting Interim Injunction:

  • The Court re-affirmed that granting of a patent does not create a presumption of absolute validity and that interim injunctions (which can restrain competitors even before final trial) are an extraordinary remedy.
  • Citing various precedents, the judgment emphasized the need for a strong prima facie case, balance of convenience, and risk of irreparable harm not mere prior grant or enforcement history.
  • Here, Natco had cleared the way via revocation actions, was already marketing the product, and the patent was close to expiration, tipping the balance against granting an injunction.

FMC v. Natco – Outcome and Directions:

The Court’s Decision:

  • No Interim Injunction was granted to FMC. The court held that on an interim, prima facie basis Natco has demonstrated a serious, credible challenge to the validity of Claim 12 of IN645. Therefore, Natco’s continued commercialization of the allegedly infringing product was not stopped pending full trial.
  • The court ordered Natco to maintain detailed records of product manufacturing and sales for possible damages, should the final trial ultimately rule in FMC’s favor.

FMC v. Natco – Conclusion:

This judgment is a milestone for Indian patent jurisprudence, especially relating to active ingredient intermediates, divisional patents, and the management of patent expiry and evergreening risks. Both innovators and generics need to closely study this order to refine their patenting and litigation strategies in India. For the wider industry and public, it underscores the critical balance courts must maintain between incentivizing innovation and ensuring prompt, fair access to technologies.

As the full trial unfolds, all eyes will remain on the High Court of Delhi for final directions on the merits meanwhile, the bar has been set higher for obtaining interim injunctions in patent cases nearing the end of their exclusivity period.

Citation:

Delhi High Court Judgement for CS(COMM) 607/2024 dated Nov 17, 2025