Upendra Nath Dass And Sons v. T.C. Martin

In the world of intellectual property, the instinct to fight back against a patent threat is natural. But what if the way you fight back actually hands the victory to your opponent? A decades-old dispute over machines used in tea manufacturing offers a sharp reminder: when it comes to defending your business against patent threats, half-measures can be more dangerous than silence.

Upendra Nath Dass And Sons, a business operating in the tea manufacturing supply chain, found itself on the receiving end of threats tied to Patent No. 63186 — a patent covering crushing machines used in tea production. The patent holder, T.C. Martin, allegedly threatened the firm with legal action over the use of such machines. Believing the patent itself was flawed, Upendra Nath Dass And Sons took the offensive and filed a suit seeking an interim injunction to stop what they characterized as groundless threats. Their position rested on two pillars: the patent was invalid, and they were not infringing it.

The plaintiffs argued that the very foundation of the threat — the patent — was legally unsound. If the patent was invalid, they reasoned, then any threat built upon it must necessarily be groundless. The defendant, T.C. Martin, countered with a procedural and substantive point that proved decisive: simply asserting that a patent is invalid is not enough. Under the relevant statutory framework, a plaintiff seeking relief from groundless threats must do more than cast doubt on the patent's validity — they must provide a clear, unequivocal statement that they have not infringed the patent in question. The legal friction centered on a deceptively simple question: what exactly must a defendant to a threat say to earn the court's protection?

The court sided with T.C. Martin. It held that a mere claim of patent invalidity is insufficient to ground a suit against alleged groundless threats. The law requires the plaintiff to unequivocally state that there has been no infringement of the patent. Because Upendra Nath Dass And Sons had not met this threshold — their denial of infringement was not framed with the required clarity and certainty — the court ruled in favor of the defendant. The interim injunction the plaintiffs sought was not granted, leaving the business exposed to the very threats it had tried to neutralize.

For founders and IP professionals, the lesson is precise and practical: if you ever face a patent threat and want to turn the tables under Section 36 of the Indian Patents and Designs Act, do not rely on attacking the patent's validity alone. You must also deliver an unequivocal, unambiguous statement that your product or process does not infringe the patent. Vague denials or arguments limited to invalidity will not suffice. When drafting your response to a patent threat, treat the no-infringement declaration as a non-negotiable element — it is the foundation upon which any successful counter-claim must be built.