New Delhi, Jan 2 (UNI) The Delhi High Court has refused to interfere with the grant of a pharmaceutical patent to Swiss drugmaker Helsinn Healthcare SA for a nausea and vomiting medication, dismissing a challenge mounted by Zydus Healthcare Ltd.
In a judgment dated December 24, 2025, Justice Tejas Karia held that the Patent Office committed no jurisdictional error and did not violate the principles of natural justice while granting the patent. The Court clarified that proceedings relating to the examination of a patent application and a pre-grant opposition are distinct and independent processes under the Patents Act.
Appearing for Zydus Healthcare, Senior Advocate Dayan Krishnan argued that the Patent Office ought to have granted the company an additional hearing after further amendments were made to the patent claims during the examination stage.
He was assisted by advocates Adarsh Ramanujan, Bitika Sharma, Vrinda Pathak, P.S. Manjunathan, Sandhya Kukreti, Shreedhar, and Parth Singh. It was contended that denial of such a hearing violated principles of natural justice.
Rejecting this submission, the Court observed that an opponent at the pre-grant stage has no right to participate in or seek a hearing during the examination of the patent application.
“A pre-grant opposition and examination are two separate and independent proceedings,” Justice Karia noted, adding that the grounds raised by Zydus had already been considered during the hearing on the pre-grant opposition. The patent in question relates to an invention titled “Compositions and Methods for Treating Centrally Mediated Nausea and Vomiting.” Helsinn Healthcare filed its patent application in April 2012 with 51 claims.
During prosecution, Helsinn sought voluntary amendments, stating that these were required to clearly define the scope of the invention. A First Examination Report was subsequently issued by the Patent Office, followed by further amendments. Zydus had filed a pre-grant opposition alleging that these amendments impermissibly expanded the scope of the claims and that mandatory provisions of the Patents Act and Rules had not been complied with. A hearing on the opposition was conducted in May 2022, after which the Patent Office reserved its decision.
After reserving orders on the opposition, the Patent Office issued a separate hearing notice to Helsinn during the examination stage, which led to additional amendments. In March 2023, the Patent Office rejected Zydus’ pre-grant opposition and granted the patent to Helsinn.
On behalf of Helsinn Healthcare, Senior Advocate Amit Sibal, assisted by advocates Pravin Anand, Dhruv Anand, Udita Patro, Dhananjay Khanna, Nimrat Singh, Smriti Nair, Saksham Dhingra, and Suditi Batra, defended the grant of the patent.
Counsel submitted that the statutory framework clearly differentiates between examination and opposition proceedings and that Zydus had no vested right to be heard beyond the pre-grant opposition stage.
Agreeing with this position, the Court held that the right of hearing available to an opponent under Rule 55 of the Patent Rules is confined to the issues raised in the pre-grant opposition. “The examination process demands a focused evaluation of the application, whereas the opposition process addresses concerns of external stakeholders,” the Court observed.
On the issue of amendments to the claims, Justice Karia ruled that there is no legal requirement for the Patent Office to pass a separate order on voluntary amendments made before the issuance of the First Examination Report. The Court also declined to entertain the writ petition on the ground of territorial jurisdiction. It held that in challenges to Patent Office orders, jurisdiction lies with the High Court within whose territorial limits the concerned Patent Office is located.
Since the patent was granted by the Mumbai Patent Office, the Delhi High Court lacked territorial jurisdiction to entertain the challenge. Finding no procedural illegality or violation of natural justice, the Court dismissed Zydus Healthcare’s petition and upheld the grant of the patent in favour of Helsinn Healthcare SA.
