'Complete Specification' Of Invention In Patent Is Sacrosanct To Determine Case Of Infringement: Delhi High Court

Justice Amit Bansal held, “Once the plaintiff has itself identified features that are essential to the suit patent in the Complete Specification, it is estopped from contending that they are not essential so as to make out a case of infringement.”

The observation comes in a patent suit filed by a city-based agrochemical company seeking an injunction to restrain the defendants from infringing its registered patent “Weedicidal Formulation and Method of Manufacture thereof” (suit patent).

The plaintiff claimed that the formulation/composition of defendants' 'Racer,', 'Trophy' and 'Jodi no.1' products was identical to the composition disclosed and claimed in the suit patent.

The defendant, on the other hand, contended that their formulation does not contain any pigment, dyeing agent, or colouring substance, which the plaintiff has explicitly claimed to be a novel and essential component of the suit patent. Thus, in the absence of a 'dyeing agent or pigment', the defendants' product differs substantially and does not fall within the scope of the suit patent.

The Plaintiff, however, claimed that 'dye or pigment' is merely an optional 'adjuvant/ excipient' and does not constitute an essential element of the invention.

Thus, the issue before the Court was whether the 'dyeing agent or pigment' is an essential element of the suit patent and whether the absence of a pigment in the defendants' products would still constitute a violation of the suit patent.

At the outset, the High Court referred to a Co-ordinate Bench decision in Ecomax Solutions (P) Ltd. v. Energeo Building Solutions which held that in an infringement proceeding, the Complete Specification of the suit patent is sacrosanct. It was further held that the plaintiff is bound by what the plaintiff itself claimed to be inventive.

It observed, “The Complete Specification plays an important role in determining the 'essential features' and the 'inventive concept' of a patent. To determine the underlying problem that existed in the prior art and the manner in which the same is sought to be solved by the 'inventive concept' of the suit patent, the Court shall be required to examine the complete specification, claims as well as the prosecution history of the suit patent.”

It then referred to the 'Complete Specification' dated 7th March 2011 filed on behalf of the plaintiff, in which it was claimed that inclusion of a dye is essential to the invention for assisting farmers by visual identification of treated weeds.

Thus, the Court observed, “From the claim mapping of the suit patent with the defendants' product, it is clear that the independent claims of the suit patent cover a 'dyeing agent or pigment', whereas the products of the defendants do not contain a 'dyeing agent or pigment'. Therefore, this is not a case where 'literal infringement' has been made out.”

The Court also tested whether the infringement is made out on the basis of the 'Doctrine of Equivalents' and prima facie answered in the negative.

As such, it refused the interim injunction and listed the suit for hearing on July 30.

Appearance: Mr. Dayan Krishnan, Senior Advocate with Mr. Gaurav Barathi, Ms. Srika Selvam, Ms. Rasya Rawal and Mr. Harsh Gupta, Advocates for Plaintiff; Mr. J. Sai Deepak, Senior Advocate with Mr. Ajay Amitabh Suman, Mr. Rishi Bansal, Mr. Deepak Srivastava, Mr. Rishabh Gupta and Ms. Daesha Mehta, Advocates for Defendants

Case title: Crystal Crop Protection Limited v. Safex Chemicals India Limited & Ors.

Citation: 2025 LiveLaw (Del) 544

Case no.: CS(COMM) 196/2024

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