Patent revocation – Identity of claims in suit patent and prior art is only required for Section 64(1)(a) to apply

The Delhi High Court has observed that Section 64(1)(a) of the Patents Act, 1970 would apply only where the claim in the suit patent is claimed in an earlier granted patent. The Court noted that what matters is not the invention per se, but the extent to which the invention is claimed in the claim of the suit patent, as there is no reference to disclosure, or coverage, or obviousness, or ‘newness’ or novelty. It was also, in this regard, noted that the requirement of a claim-to-claim comparison was also as per Section 13(1)(b), and that the ‘person skilled in the art’ has no role to play, while applying Section 64(1)(a).

With respect to Section 63(1)(f), the Court was of the view that at the interim stage (Order XXXIX stage), the Court is only required to satisfy itself, prima facie, that a credible challenge to the validity of the claims in the suit patent, as obvious from the disclosures contained in prior art, has been made out. According to the Court, a detailed examination (as prescribed in the 2016 decision in F. Hoffmann-La Roche Ltd. v. Cipla Ltd.) on the obviousness of the claims in a suit patent is not required in such cases. 

On the facts of the case, the Division Bench upheld the findings of the Single Bench that Semaglutide (the drug in the suit patent) was obvious to a person skilled in the art from the complete specifications, and the teachings contained therein, in IN 275964. However, according to the Court, a credible challenge to the validity of the suit patent would be relatable not to sub-clause 64(1)(a), but to sub-clauses 64(1)(e) and (f).

Patent about to expire – Courts should apply principles of balance of convenience and irreparable loss before interfering 

Further, in this appeal against dismissal of application (filed by the patentee) for interim injunction, where only two months were left for the suit patent to expire even when the judgement was reserved, the High Court also observed that in such cases the Courts should also consider whether, applying the principles of balance of convenience and irreparable loss, it should interfere. The defendant in Novo Nordisk A/S v. Dr. Reddys Laboratories Limited & Anr. [Judgement dated 9 March 2026] had challenged the validity of the claims in the suit patent.