Delhi High Court Upholds Permissibility Of Claim Amendments: Albemarle Corporation V. Controller Of Patents

Introduction

In Albemarle Corporation v. The Controller of Patents [1] [C.A.(COMM.IPD-PAT) 19/2022], the Hon’ble Delhi High Court (hereinafter “the Court”) reaffirmed that amendments to patent claims are permissible at the appellate stage under the Indian Patents Act, 1970 (hereinafter “the Act”). The Court vide its decision dated July 7, 2025, permitted Albemarle Corporation (hereinafter “Appellant”) to file an auxiliary set of claims via an application being I.A. 35045/2024 and remanded the matter to the Patent Office for fresh consideration of the Appellant’s patent application in light of the amended claims, in accordance with law.

Background

The Appellant,  a U.S.-based chemical company, filed an appeal under Section 117A of the Act against a refusal order (hereinafter “impugned order”) dated May 12, 2021, issued by the Controller of Patents (hereinafter “Respondent”), refusing the Indian Patent Application No. 2897/DELNP/2012, titled as “Solvent Systems Having No Flash Point And Methods Using Such Solvent Systems For Dissolving Rigid Polyurethane Foams”, under Section 15 of the Act.  

The Application was refused on the grounds that the subject matter of the claims lacked novelty over cited document D4, lacked inventive step in view of the cited documents D1 to D4, and non-fulfilment of enablement requirements under Section 10(4) of the Act.

Interestingly, during the pendency of the appeal before the Court, the Appellant did not contest the impugned order. Instead, it only sought the permission to amend the claims by filing an auxiliary claim set, thereby restricting the scope of the invention only to the process.

Key issues before The Hon’ble Court

·       Whether amending of claims is permissible at the appeal stage under the Indian Patents Act?

·       Whether the scope of such permissible amendments comply with Section 59 of the Act?

Arguments set forth by the Appellant and the Respondent

The Appellant argued that the auxiliary set of claim was submitted to facilitate the expeditious disposal of the matter. It was submitted by the Appellant that the amendments merely restricted the scope of the claims to the process aspect while disclaiming the broader claims for the solvent system (a product).

Conversely, the Respondent contended that amendments via auxiliary set of claims cannot be allowed at the appellate stage and justified the impugned order.

Observations and Findings of the Court

At the outset, the Court noted that the Appellant did not contest the impugned order and confined its submissions only to the aspect of allowing the auxiliary set of claim to restrict the scope of the claims to the process aspect for cleaning polyurethane foam from an article.

The Court further observed that through the auxiliary set of claims, the Appellant had reduced the scope solely to a process without introducing any new matter beyond what was already disclosed in substance in the originally filed specification. The Court also emphasized that Sub-Section (1) of Section 58 of the Act permits amendments to the specification in proceedings before the High Court.

Therefore, in considering the maintainability of the Appellant's application for allowance of the auxiliary claim set at the appellate stage, the Court observed that the Patents Act does not enforce any express bar on amending patent application or specification during appeal proceedings provided the amendments fulfil the requirements under Section 59 of the Act and the amended claims are not inconsistent with the earlier Claims in the original specification.

Hon’ble Court’s Decision

The Hon’ble Court held that amendments to claims are permissible even at the appellate stage, provided they do not introduce new subject matter and are consistent with the originally filed claims. Accordingly, the Court found that the Appellant’s auxiliary claim set is allowed as it fall wholly within the scope of the originally filed claims.

The Court also relied upon its previous position in Societe Des Produits Nestle v Controller of Patents and Designs & Anr[2], wherein it was held that “..there is no provision in the Act, which specifically bars the amendment of a patent specification at the appellate stage”

Further, reliance was placed upon the decision in Nippon A & L Inc. Versus Controller of Patents[3] and W R Grace and Co. Conn. Versus Controller of Patents[4], wherein it was held that:

“It is a well-settled position in law that amendments that narrow down or restrict the scope of the claims to address objections raised by the Patent Office, or facilitate grant, are permissible, if the amendments are within the scope of the patent specification, and the originally filed claims.”

Thus, the Hon’ble Court allowed the appeal to the extent that the auxiliary claim set were taken on record and directed that the Patent Application No. 2897/DELNP/2012 be revived, in order to consider the application of the Appellant in light of the auxiliary claim set. The Court, however, did not interfere with the Patent Office’s impugned order, as it was based on the original claims and the Appellant did not challenge it.

Conclusion

This decision of the Court affirms that amendments to claims are permissible even after grant or during appellate proceedings, as long as they comply with the requirements as prescribed under Section 59 of the Patents Act.

The two-pronged test used for examining the allowability for such amendments:

·       Amendment must not introduce any ‘new matter’ that is not based on the original disclosure of the application.

·      Amended claim must fall ‘wholly within the scope of a pre-existing claim,’ ensuring that the scope of amendments is not expanded beyond its original boundaries.

A similar view was taken by the Hon’ble Delhi High Court in Cellectis v Assistant Controller of Patents and Designs[5] and Fresenius Medical Care Deutschland v Controller General of Patents, Designs and Trademarks & Anr[6], wherein the Court reviewed the auxiliary claim amendments and allowed them after a comprehensive analysis. In both cases, the court held that the amendments, constituting disclaimers or explanations, did not introduce new matter, remained within the scope of the original claims, and were supported by the specification, thus permissible under Section 59 of the Act.

Thus, this decision in Albemarle Corporation reinforces the High Court’s consistent stand on the allowability of claim amendments during appellate proceedings, establishing a consistent approach across jurisdictions and thereby promoting a balanced approach for claim amendments.

Arpita Mukherjee

Managing Associate

arpita.mukherjee@iprattorneys.com

Gunjan Garg

Associate

gunjan.garg@iprattorneys.com

References:

[1] Albemarle Corporation vs The Controller of Patents, [C.A.(COMM.IPD-PAT) 19/2022; decision dated July 7, 2025]

[2] (CA (COMM IPD- PAT) 22/2022, 2023/DHC/000774)

[3] C.A.(COMM.IPD-PAT) 11/2022

[4] C.A.(COMM.IPD-PAT) 5/2022 and I.A. 17000/2023

[5] (CA (COMM IPD-PAT) 6/2023, 2025:DHC:1466)

[6] (CA (COMM IPD-PAT) 302/2022, 2025:DHC:2778)