Headnote
Patents Act, 1970 – Sections 48, 64, 107 – Interim injunction – Patent infringement – Credible challenge to validity – Prior art – Abandoned foreign patent application – Foldable product display unit.
Held, at the interim stage in a patent infringement suit, an injunction may be granted where the patentee establishes a prima facie case of infringement and the defendant fails to raise a credible and tenable challenge to the validity of the patent. While there is no statutory presumption of patent validity, a defendant must demonstrate vulnerability through cogent prior art and proper claim mapping. Mere reliance on an abandoned foreign patent application, without establishing disclosure of all essential elements of the claimed invention or satisfying the test of obviousness, does not constitute a credible challenge. Prior user claims based on emails, presentations, invoices, or photographs require strict proof and cannot be accepted at face value at the interlocutory stage. Where the defendant’s product prima facie embodies the essential features of the patented invention and balance of convenience favours protection of statutory monopoly, interim injunction is justified to prevent irreparable harm to the patentee.
Court’s decision
The Delhi High Court allowed an application for interim injunction in a commercial patent infringement suit concerning a patented foldable product display unit. The Court restrained the defendant from manufacturing, selling, or dealing in the impugned foldable display units during the pendency of the suit. It held that the plaintiffs had successfully demonstrated a prima facie case of infringement, while the defendant failed to raise a credible challenge to the validity of the suit patent at the interlocutory stage.
Facts
The plaintiffs are engaged in the business of manufacturing and marketing retail display systems, including foldable product display units. The suit concerned Indian Patent No. IN 533643 titled “A Foldable Product Display Unit”, granted in April 2024 after a prolonged prosecution history involving examination and a failed pre-grant opposition by the defendant. The patented invention claims a specific configuration of interconnected movable shelves, back panels, side panels, foldable joints, and locking mechanisms enabling the display unit to fold compactly while allowing shelves to move in tandem.
In August 2024, the plaintiffs discovered that foldable display units supplied by the defendant to a retail brand closely mirrored the patented configuration. Photographs, invoices, and product samples indicated that the impugned products embodied the essential features of the suit patent. Consequently, the plaintiffs instituted a commercial suit seeking permanent injunction and filed an application for interim relief.
Issues
The Court was required to determine whether the plaintiffs had made out a prima facie case of patent infringement, whether the defendant had raised a credible challenge to the validity of the suit patent, and whether the balance of convenience and irreparable harm justified grant of an interim injunction.
Plaintiffs’ arguments
The plaintiffs argued that the defendant’s foldable display units incorporated each essential element of Claim 1 of the suit patent, including interconnected movable shelves that fold and unfold in tandem and side panels that move together in the same direction after folding. It was contended that the defendant had already opposed the patent during prosecution and failed, and that no post-grant opposition had been pursued. The plaintiffs submitted that alleged prior user documents relied upon by the defendant were self-serving and unproven. Reliance on an abandoned US patent application as prior art was criticised as irrelevant and insufficient to undermine the novelty and inventive step of the granted claims.
Defendant’s arguments
The defendant resisted the injunction by asserting lack of patent validity, disputing ownership and inventorship, alleging defects in patent forms, and claiming prior use of similar foldable display systems long before the priority date. It relied heavily on a published but abandoned US patent application as prior art, contending that the suit patent was obvious and anticipated. The defendant also argued that there is no presumption of validity in favour of a granted patent and that the balance of convenience favoured continuation of its long-standing business activities.
Analysis of the law
The Court reiterated settled principles governing interim injunctions in patent matters. While grant of a patent does not guarantee its validity, the defendant must raise a substantial and credible challenge to resist interim protection. The threshold at this stage is vulnerability, not final determination of invalidity. The Court emphasised that prior art must disclose all essential elements of the claimed invention and must be properly mapped against the claims. Obviousness must be assessed using the structured test laid down by precedent, focusing on the perspective of a person skilled in the art.
Precedent analysis
Relying on decisions of the Supreme Court of India and prior rulings of the Delhi High Court, including Bishwanath Prasad Radhey Shyam v. Hindustan Metal Industries, TEN XC Wireless Inc. v. Mobi Antenna Technologies, and F. Hoffmann-La Roche v. Cipla, the Court reiterated that absence of presumption of validity does not dispense with the requirement of a credible challenge. Mere assertion of prior art or prior use without rigorous proof is insufficient at the interim stage.
Court’s reasoning
Applying the settled tests, the Court found that the defendant’s reliance on an abandoned foreign patent application did not, by itself, establish anticipation or obviousness, particularly in the absence of detailed claim mapping and demonstration of identical functionality. The Court further held that documents such as emails, invoices, and presentations relied upon for prior use would require strict proof at trial and could not dislodge the plaintiffs’ prima facie case at the interlocutory stage. Given the admitted similarity between the impugned products and the patented configuration, the Court concluded that infringement was prima facie established.
Conclusion
The High Court granted an interim injunction restraining the defendant from dealing in the impugned foldable display units. It held that permitting continued manufacture and sale would erode the statutory monopoly conferred by the patent and cause irreparable harm to the plaintiffs.
Implications
The ruling reinforces Delhi High Court’s patent jurisprudence favouring protection of granted patents at the interim stage where infringement is prima facie shown and validity challenges lack substance. It clarifies that abandoned foreign patent publications can constitute prior art but must satisfy rigorous tests of disclosure and obviousness. The decision provides valuable guidance on the evidentiary burden for prior user claims and credible challenges in patent injunction matters.
Case-law references
- Bishwanath Prasad Radhey Shyam v. Hindustan Metal Industries – No presumption of patent validity.
- TEN XC Wireless Inc. v. Mobi Antenna Technologies – Meaning of credible challenge at interim stage.
- F. Hoffmann-La Roche Ltd. v. Cipla Ltd. – Structured test for obviousness and inventive step.
- 3M Innovative Properties Ltd. v. Venus Safety – Degree of credible challenge after failed opposition.
FAQs
1. Is an interim injunction automatic once a patent is granted?
No. The patentee must still establish prima facie infringement and absence of a credible validity challenge.
2. Can an abandoned foreign patent application be used as prior art?
Yes, if published before the priority date, but it must disclose all essential features of the claimed invention.
3. Are invoices and emails sufficient to prove prior use in patent cases?
No. Prior use requires strict proof of identical technical features and cannot be presumed at the interim stage.