Brief Head Note
Interim injunction refused in IN’645 despite admitted infringement; patent held highly vulnerable. The Court refused to grant an interim injunction, holding that the patent is highly vulnerable on multiple grounds: prior claiming by FMC’s own earlier patent IN 269104, lack of novelty and inventive step over cited prior art. Relying on the “credible challenge” principle laid down in F. Hoffmann-La Roche v. Cipla, Ericsson v. Lava, and Interdigital v. Xiaomi, the Court observed that only 19 days of patent life remained, Natco had already launched the product after obtaining regulatory approvals, and monetary compensation would suffice for the short remaining period.
Facts
The case revolves around a patent dispute in the agrochemical industry between FMC Corporation (an American company) along with its group companies (collectively called the plaintiffs) and Natco Pharma Limited (an Indian pharmaceutical and agrochemical company, referred to as the defendant).
The plaintiffs own Indian Patent No. 298645 (called the suit patent), granted in 2018, which is titled “Method for Preparing N-Phenylpyrazole-1-Carboxamides”. This patent covers a process to make certain insecticides, and importantly, Claim 12 protects a specific chemical compound known as the Compound of Formula 3, which is an intermediate chemical used in that process. This intermediate is 2-amino-5-cyano-N,3-dimethylbenzamide – basically a building block chemical needed to produce the final insecticide called Cyantraniliprole.
The plaintiffs discovered that Natco was manufacturing and selling an insecticide product called Cyantraniliprole 10.26% OD (Oil Dispersion) using this exact patented intermediate. Natco openly admitted in court that it was using this intermediate in its manufacturing process.
The patent is set to expire on 6 December 2025, so very little time was left when the judgment came.
Earlier Litigation History
- Long history of disputes between FMC and Natco over Chlorantraniliprole & Cyantraniliprole
- Earlier cases focused on process claims (Claims 1–11)
- Courts had denied injunction earlier since Natco’s process was different enough
- Current dispute strictly concerns **Claim 12 – the intermediate compound**
Procedural Detail
The suit was filed in 2024. The plaintiffs moved an application (I.A. 34151/2024) under Order 39 Rules 1 & 2 CPC for interim injunction.
| Event | Details |
|---|---|
| Natco Product Launch | Already launched before hearing |
| Disclosure Ordered | 1 August 2025 (sales + stock disclosed via affidavit) |
| Judgment Delivered | 17 November 2025 (19 days before expiry) |
| Patent Expiry | 6 December 2025 |
Natco had earlier filed a revocation petition and secured regulatory approvals. Parallel matters from Chandigarh were transferred to Delhi High Court.
Dispute
The core dispute:
- Natco admitted infringement → using the patented intermediate
- FMC argued injunction is automatic because patent validity extends till 6 December 2025
- Natco argued → patent is invalid on multiple grounds:
- Lack of novelty
- Obviousness
- Prior claiming by IN 269104 (double patenting)
- Section 3(d): mere new form
- Section 3(e): mere admixture
- Insufficient disclosure / too broad claims
Natco → “We filed revocation, so we cleared the way — and patent has only days left.” FMC → “Natco is a habitual infringer; admitted infringement requires injunction.”
Detailed Reasoning of the Court
The court reiterated the rule from major patent cases:
- Where infringement is admitted → burden shifts to defendant
- If defendant raises a credible challenge to validity → no injunction
Grounds of Invalidity Examined
1️⃣ Prior Claiming / Double Patenting
The intermediate was already claimed in FMC’s earlier patent IN 269104.
The court held: serious triable issue → Section 64(1)(f).
2️⃣ Lack of Novelty
Prior art documents D1–D12 showed similar compounds. D4 & D6 → close structural matches
3️⃣ Obviousness
Pozzoli test → skilled person could easily derive the same intermediate.
4️⃣ Section 3(d) – Mere New Form
No efficacy data → vulnerable.
Section 3(d) applies to intermediates too → Novartis ruling followed.
5️⃣ Section 3(e)
This ground was not accepted.
6️⃣ Insufficient Disclosure / Inoperability
Patent failed to guide manufacture where R3 ≠ methyl → serious issue exists.
Thus, patent is “highly vulnerable”.
Court Relied on Major Judgments
- F. Hoffmann-La Roche v. Cipla 2015 – credible challenge rule
- Telefonaktiebolaget Ericsson v. Lava – vulnerability test
- Interdigital v. Xiaomi 2024 – short patent life against injunction
- Nokia v. Oppo – strong prior art → no injunction
- Avery Dennison v. Konti Continental – overlapping patents = vulnerable
- Bristol Myers Squibb v. J.B. Chemicals – damages preferable if expiry near
Irreparable injury not established:
- Only 19 days patent life remaining
- Natco stock would otherwise be wasted
- Money damages sufficient
Decision
Application I.A. 34151/2024 was dismissed.
No interim injunction was granted.
Case Details
- Case Title: FMC Corporation & Ors. Versus Natco Pharma Limited
- Judgment Date: 17 November 2025
- Case Number: CS(COMM) 607/2024
- Neutral Citation: 2025:DHC:10092
- Court: High Court of Delhi
- Hon’ble Judge: Ms. Justice Mini Pushkarna
Disclaimer
The information shared here is intended to serve the public interest by offering insights and perspectives. However, readers are advised to exercise their own discretion when interpreting and applying this information. The content herein is subjective and may contain errors in perception, interpretation, and presentation.
Written By
Advocate Ajay Amitabh Suman, IP Adjutor [Patent and Trademark Attorney], High Court of Delhi
