Summary: Take heart! Amending patent claims on appeal in India is not a lost cause. A recent decision of the Delhi High Court helps identify strategies for patent applicants to refine claims and overcome objections. It's often not too late.
When appealing a Controller's order rejecting a patent, it was long understood that the appeal should be limited to only highlighting defects in the order. The appellant would have to go through the entire litigation life cycle of the appeal, and rest on the expectation that the court would reject the order and keep the patent application alive. Now, consider that many orders of rejection are because the Controller is not satisfied with the claims accompanying a patent specification. Assuming the court disagrees with the Controller, a shortened litigation and prosecution process would ideally allow the patent applicant to amend the claims suitably. Unfortunately, in Indian patent practice, it was assumed that claim amendments during the appellate stage were not permissible. So, this quicker – and logical – route to patent grant was not possible for the longest time.
This position has changed considerably in recent times. Over multiple decisions in recent years, the Delhi High Court has swiftly and radically undone prevailing assumptions and practices, significantly impacting patent prosecution and litigation costs, timelines, and prospects. This reform started with Societe Des Produits Nestle SA Versus Controller of Patents and Design and Another (1 2023 SCC OnLine Del 582), when the Delhi High Court held that amendments could also be carried out during the appellate stage, so long as two criteria were met: firstly, the amendments must fulfil the requirements under Section 59 of the Patents Act, 1970 ("the Act"); and secondly, the amended claims must be consistent with the original claims.
This was clarified further recently by the Delhi High Court. In Albemarle Corporation vs The Controller of Patents in [C.A.(COMM.IPD-PAT) 19/2022, I.A. 10452/2022 & I.A. 35045/2024, decision dated 7 July 2025], the Court allowed a patent applicant to submit amended claims in an appeal against a Controller's order, instead of challenging the order itself.
The dispute
The appeal was filed under Section 117A of the Act against a Controller's order rejecting the grant of Indian patent application No. 2897/DELNP/2012 titled "Solvent Systems Having No Flash Point And Methods Using Such Solvent Systems For Dissolving Rigid Polyurethane Foams". The application was refused under Section 15 on grounds that the claimed invention lacked novelty and inventive step in view of four prior art documents.
While the appeal was pending, the Appellant also filed an application before the Court to submit an auxiliary set of claims. Via these amendments, the appellant restricted their claims to the process aspect for cleaning polyurethane foam from an article. Interestingly, the rejected claims set also included four process claims (one independent claim and 3 dependent claims). A comparison of the rejected independent process claims and the process claims in the auxiliary claim set is useful in this context.
| Rejected Independent Process Claims | Auxiliary Process claims |
|---|---|
| 5. A process for cleaning polyurethane foam from an article, said process consisting of: (i) contacting the polyurethane foam with a solvent system produced by combining components consisting of: (a) from 20 wt% to 90 wt% of a brominated compound, (b) from 10 wt% to 80 wt% of an alcohol consisting of a primary alcohol and/or secondary alcohol, and (c) from 0.05 wt% to 6.0 wt% of a stabilizer consisting of an epoxide, a nitroalkane, and/or an ether, wherein the amounts of the brominated compound, the alcohol, and the stabilizer are selected so that the solvent system has no flash point and when used for removing polyurethane foam from a surface produces a used solvent having essentially no gel formation; and (ii) thereby producing used solvent, wherein there is essentially no gel formation in the used solvent. | 5. 1. A process for cleaning polyurethane foam from an article, said process consisting of: (i) contacting the polyurethane foam with a solvent system produced by combining components consisting of: (a) from 20 wt% to 9089.05 wt% of a brominated compound, (b) from 10 wt% to 8079.05 wt% of an alcohol consisting of a primary alcohol and/or secondary alcohol, and (c) from 0.05 wt% to 6.0 wt% of a stabilizer consisting of an epoxide, a nitroalkane, and/or an ether, wherein the amounts of the brominated compound, the alcohol, and the stabilizer are selected so that the solvent system has no flash point and when used for removing polyurethane foam from a surface produces a used solvent having essentially no gel formation; and (ii) thereby producing used solvent, wherein there is essentially no gel formation in the used solvent. |
The Respondent objected to the application, arguing that amended claims could not be allowed at the appellate stage. The Appellant said that this auxiliary claim set was filed to speed up disposal. Notably, the auxiliary claims narrowed the scope of the existing claims, focusing solely on the process aspect of cleaning polyurethane foam from an article.
The decision
The Court made several pertinent observations:
- The Appellant had not challenged the Controller's order and had restricted themselves only to seeking permission for allowing amendments.
- The amended claims were narrower in scope than the original claims (i.e., claims that had been rejected). Also, the auxiliary claim set did not introduce anything beyond that disclosed in the original specification.
- Relying on Nestle (supra), the Court said the Act does not impose any express bar on the amendment of a patent application or specification during appellate proceedings.
- By amending the claims to focus on a process, the Appellant has effectively reduced their scope, which fell entirely within the boundaries of the original claims.
- Citing Nippon A&L Inc. v. Controller of Patents (2022 SCC OnLine Del 1909) and W.R. Grace and Co. Conn. v. Controller of Patents (2023 SCC OnLine Del 5456), the Court reiterated that amendments limiting claim scope to address Patent Office objections are permissible if they fall within the original specification and claims.
Finding no evidence that the auxiliary claim set had contravened Section 59 of the Act, the Court allowed the application, and took the auxiliary claims on record, remanding the matter to the Patent Office to examine the amended claims. Effectively, this decision revived the patent application, and gave it a second life.
Conclusion
The Nestle (supra) decision marked a foundational change in patent practice and prosecution, with aggrieved patent applicants now being permitted to file claim amendments in appeal directly. The present case, i.e., Albemarle (supra), has reinforced this position, and clarified that applicants have a potential avenue to revive their patent applications by addressing the Controller's concerns through amended claims, rather than pursuing a potentially lengthy and complex, full-blown challenge to the order. Patent applicants who are open to the idea of amending claims would do well to pursue this line of challenge, and optimise for time and cost in securing their patent rights.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
