Species patent is vulnerable to revocation if teachings in genus patent enable a person skilled in the art.

The Appellant (Novo Nordisk) holds Indian Patent 262697 (IN’697) for "Semaglutide," an anti-diabetic drug

In 2024, the Appellant discovered that the Respondents were importing Semaglutide and filed an infringement suit in 2025

The suit patent is set to expire on March 20, 2026

The Respondents contested the suit by invoking Section 107(1) of the Patents Act, 1970, raising a "credible challenge" to the patent’s validity based on a prior Genus Patent, IN 275964 (IN’964)

A Single Judge rejected the Appellant’s application for an interlocutory injunction on December 2, 2025, finding the patent vulnerable to revocation under Section 64

The Appellant appealed this rejection.

The court applied the "Wander Standard" from Wander Ltd v. Antox (India) Pvt Ltd, which restricts appellate interference in discretionary interlocutory orders unless the lower court acted arbitrarily or perversely

Regarding patent law, Section 107(1) of the Patents Act, 1970 allows any ground for revocation under Section 64 to be a defense in an infringement suit

The court relied on F. Hoffmann-La Roche Ltd v. Cipla Ltd (Roche-I), establishing that a defendant need only show a "credible challenge" or "vulnerability" of the patent at the interim stage

For obviousness, the court referenced Section 2(ja) regarding "inventive step" and the "person skilled in the art" (PSITA) test as interpreted in Roche-II, while also applying the "person in the know" test for common inventors as established in AstraZeneca AB v. Intas Pharmaceuticals Ltd

The Court first noted the lack of "irreparable loss" to the Appellant, as the patent was only two months from expiry when judgment was reserved

On the merits, the Court found that while the Single Judge slightly conflated "prior claiming" (Section 64(1)(a)) with "obviousness" (Section 64(1)(f)), the factual findings strongly supported a credible challenge under the latter

The Appellant admitted that the only difference between Example 61 of the prior Genus Patent (IN’964) and Semaglutide was the substitution of the amino acid 'Ala' with 'Aib' at the 8th position

The Court reasoned that since Claim 16 of the Genus Patent specifically taught that 'Aib' was a preferred substitution at that position, a "person in the know" (given five inventors were common to both patents) would find the transition to Semaglutide obvious

Thus, the suit patent was prima facie vulnerable to revocation for lack of an inventive step.

It held that the Respondents successfully established a credible challenge to the validity of the suit patent under Section 64(1)(f) (obviousness)

The Court further emphasized that in cases where a patent is on the verge of expiry and a credible challenge is raised, the balance of convenience and the principle of avoiding "mini-trials" at the interim stage weigh against granting an injunction

The Respondents remain bound by their earlier undertaking not to sell in India until the patent expires