The Delhi High Court decided an important case on patent law in Novo Nordisk A/S v. Dr. Reddy’s Laboratories Ltd. The dispute involved Semaglutide, a widely used drug for diabetes and obesity. It addressed an important issue: can a patentee/ Plaintiff obtain an injunction if the Defendant, with knowledge of the Plaintiff’s patent rights, proceeds with production/ manufacturing of the patented drug,without first initiating revocation or non-infringement proceedings. Notably, the Delhi High Court declined to release the Defendant from its undertaking of not selling the patented drug in India as it had begun manufacturing/ production without “clearing the way”, despite being fully aware of the suit patent. The Court, however, allowed the Defendant to export to jurisdictions where the Plaintiff holds no patent rights. The judgment serves as an important precedent in determining the inter-relationship between injunctive relief and patent validity challenges.
Background
The dispute concerned Indian Patent No. 262697 (“Suit Patent”), titled “Acylated GLP-1 Analogs Comprising Non-Proteogenic Amino Acid Residue”, which covers and claims Semaglutide. This patent application was filed in India in July 2007, granted in September 2014, and is set to expire on March 20, 2026. The compound is marketed globally under the brand names Ozempic, Wegovy, and Rybelsus.
In October 2024, the Plaintiff discovered that certain Indian companies were importing and possibly manufacturing Semaglutide. Upon investigation, it was found that the Defendant was importing and exporting the compound in significant quantities, suggesting commercial use rather than research. The Plaintiff issued a cease-and-desist notice in May 2025, after which the Defendant filed a revocation petition challenging the validity of the Patent. The Plaintiff then instituted the present suit, seeking an interim injunction under Order XXXIX Rules 1 and 2 of the Code of Civil Procedure, 1908, to restrain infringement.
During the initial hearing on May 29, 2025, the Defendant acknowledged manufacturing Semaglutide and additionally undertook not to sell the drug in India, but it reserved the right to export to jurisdictions where the Plaintiff does not possess a relevant patent. The Defendant clarified that they do not have a sale license in India. The Court recorded this undertaking and did not restrain exports. The Plaintiff appealed this order, and the Division Bench directed the Single Judge to decide the interim injunction application.
Issues before the Court
The Delhi High Court was tasked with determining whether the Defendant should be prohibited from manufacturing Semaglutide in India until the Plaintiff’s Patent expires in March 2026. Although the Defendant had undertaken not to sell the drug in India and to export solely to jurisdictions where the Plaintiff did not hold a patent, the Plaintiff sought a complete injunction against manufacturing.
This raised an important question: should the Court grant interim relief when infringement is acknowledged, but the Defendant has argued that the patent is invalid under Section 107(1) of the Act? According to Section 107(1) of the Act, a ground that can result in revocation of a patent (under Section 64) can also be ground for defence in a patent infringement suit. As per Section 107(1), even if infringement is apparent, a defendant can argue that the patent itself is invalid. The Court, therefore, had to determine whether the Defendant had raised a “credible challenge” to the validity of the Suit Patent. If the Court finds that the patent itself could be invalid, then it may refuse an injunction despite admitted infringement.
The Court, therefore, had to determine whether the Defendant had raised a credible challenge under Section 64 of the Act, which can result in patent revocation. The Defendant raised this challenge on grounds of anticipation by prior claiming, prior publication, and obviousness.
Findings and Reasoning
The Court clarified that under Section 107(1) of the Patents Act, a defendant in an infringement suit may raise patent revocation as a defence under Section 64. This means that even if the defendant is producing a patented product, they can argue that the patent itself is invalid. Indian law does not presume a granted patent to be valid, as Section 13(4) explicitly states that examination and grant do not guarantee validity. Therefore, the Court’s first task was to apply the “credible challenge” test to determine whether the defendant presents a serious, non-frivolous argument that the patent may be invalid. If found credible, the Court refuses interim relief and allows the matter to go to trial. This principle ensures that injunctions do not unfairly enforce patents that may later be revoked.
Anticipation by prior claiming under Section 64(1)(a)
The Plaintiff’s position was that the genus patent did not contain an enabling disclosure of the Semaglutide compound. They argued that coverage is not disclosure. The Court examined the claims and examples of Genus Patent and compared them with the Suit Patent. It found that Example 61 of Genus Patent was extremely close to Semaglutide, differing only by one substitution at position 8 (‘Ala’ replaced by ‘Aib’). Importantly, the Genus Patent itself taught that Aib substitution was preferred at that position. This meant that a person skilled in the art could derive Semaglutide from Genus Patent without inventive effort. The Court also noted that Claim 16 of the Genus Patent also enabled substitution of Ala with Aib, leading directly to Semaglutide. The Court also noted the Plaintiff’s own filings (Form 27 in India and foreign patent term extensions), where the Plaintiff linked Semaglutide to Genus Patent. These admissions reinforced the view that the Suit Patent was prima facie vulnerable on the ground of prior claiming.
Determination of Priority Date of the Genus Patent
The Court also had to determine what the correct priority date of the Patent would be, to ascertain what would constitute prior art. The Genus Patent was published on March 31, 2005. The Plaintiff claimed priority date of March 18, 2005, for the Suit Patent, meaning that the Genus Patent (also published in March 2005) could not be a prior art for invalidating the Suit Patent. However, the European Opposition Division (“EOD”), in a related proceeding, held that the relevant claim of the European counterpart was not entitled to the March 2005 priority and instead had a priority of March 20, 2006. While the Court did not conclusively decide the priority date, it accepted the EOD’s finding as a relevant fact for prima facie analysis, treating the Genus Patent as prior art for the interim stage.
This allowed the Court to consider the Genus Patent as prior art when assessing anticipation and obviousness.
Anticipation by prior publication under Section 64(1)(e)
The Defendant further argued that the Suit Patent could be invalidated for anticipation by prior publication under Section 64(1)(e) of the Patents Act, 1970. The Court held that the Genus Patent, read as a whole, disclosed the essential features of Semaglutide. It was not necessary for IN’964 to use the exact name “Semaglutide”; what matters is whether the prior patent taught the combination of features that make up the invention. Here, the Genus Patent’s claims and examples, combined with its teaching on substitutions, provided enough information for a skilled person to arrive at Semaglutide without undue experimentation. Therefore, the Court found a credible case of anticipation.
Obviousness under Section 64(1)(f)
The Court then considered whether Semaglutide involved an inventive step. Indian law defines inventive step as something not obvious to a person skilled in the art. Applying the five-step test from F. Hoffmann-La Roche v. Cipla, 2015 SCC OnLine Del 13619, the Court identified the inventive concept to be a GLP-1 analogue modified for extended half-life and less frequent dosing. It then looked at prior art (the Genus Patent) and common general knowledge (scientific literature). These sources taught that substituting Aib at position 8 improves stability and half-life. The only difference between Example 61 and Semaglutide was this substitution, which the Genus Patent explicitly suggested. Hence, the Court concluded that a skilled person would have had a reasonable expectation of success in making Semaglutide. This made the Suit Patent prima facie obvious.
Basis its findings under Section 64(1)(a), 64(1)(e) and 64(1)(f), the Court found a strong prima facie case exists for a credible challenge to the validity of the Suit Patent.
Balance of Convenience and Irreparable Injury
The Court held that the balance of convenience favoured the Defendant, allowing manufacturing and export under strict conditions. It, therefore, refused a blanket injunction, but directed the Defendant to maintain detailed accounts and prohibited sales in India. The Court also emphasised that while it permitted manufacturing and export to non-patent jurisdictions, it refused to relax the Defendant’s undertaking not to sell in India. This was because the Defendant had failed to “clear the way” before commencing manufacturing, which is a principle in patent law, requiring a party, aware of a potentially blocking patent, to first challenge its validity or seek a declaration of non-infringement before launching its product.
Considering the above, the Court dismissed the interim injunction application. It permitted the Defendant to continue manufacturing and exporting Semaglutide to non-patent jurisdictions, subject to maintaining accounts, while restraining sales in India.