Scope of Patent Amendments under Indian Patent Law


The Indian Patents Act, 1970 (the Act) allows Applicant for a Patent or a Patentee to make amendments in the application for Patent, or the complete specification, or any document related thereto, both before grant and after the grant of the patent. Even though the Act has provided specific provisions relating to the scope of the amendment, the interpretation of these provisions varies across the Controllers in India. This article will discuss the present position in India with regard to the permissible scope of amendments to the patent application before grant in light of the recent judgment of the Delhi High Court in the matter of “Nippon A&L Inc. v. The Controller of Patents”.

Nippon A&L Inc. v. The Controller of Patents[1]

The brief facts of the case are that the Appellant had filed a national phase patent application in India, seeking protection for “copolymer latex”. The claims were drafted in a “product by process” format characterized by the features of both the product and the process. In the First Examination Report, the Controller objected to the claims and held that the “Scope for which protection has been sought for product or the for process is not clear from the wording “obtained by emulsion polymerization…” as used in claims 1 and 4. Similarly claims 6 and 7 are also not clear with respect to the wording “the emulsion polymerization is carried out…” Appellant filed a response to the First Examination Report along with an amended set of claims. However, the objection regarding lack of clarity in the claims was maintained in the hearing notice.

During the hearing phase, the Appellant also proposed amending the claims, from ‘product by process’ format to ‘process only’ claims to render the claims clearer and more definite. The Appellant submitted the amended claims and contended in the written submissions that it seeks to amend the claims by way of explanation to improve clarity and definitiveness. It was further claimed by the Appellant that the amended claims were in complete compliance with the provisions of Sections 57(6), 59(1), and 10(4)(c) of the Act.

However, the Deputy Controller of Patents rejected the patent application on the ground that the new set of claims was beyond the scope of the original claims and that the amended claims are lacking inventive step. Aggrieved by this order, the Appellant preferred an appeal before the Delhi High Court.

Issues before the Court

The issue before the Court was, “whether the claims as originally filed could have been amended into method claims by the Appellant?”

Rules and/or Law

The issue before the court is pertaining to Section 59(1) of the Act, which provides that an amendment of an application, specification, or any document related thereto would be permissible only if the following conditions are satisfied:

(i) The amendment has to be by way of disclaimer, correction or explanation;

(ii) The amendment has to be for the purpose of incorporation of actual facts; and

(iii)(a) The effect of the amendment ought not to be to amend the specification to claim or describe any matter which was not disclosed in substance or shown in the originally filed specification; and

(iii)(b) The amended claims have to fall within the scope of claims as originally filed.

Thus, for an amendment to be allowed all conditions have to be satisfied. Any amendment falling foul of (i), (ii), (iii)(a) or (iii)(b) above cannot be allowed.

Contentions of the Appellant

The Appellant contended that the “original claims which were drafted, were “product by process” claims that have been amended and the claims were restricted to method claims, i.e., process claims. This amendment cannot be held to be beyond the scope of the original claims as the original claims contained both, product as also process claims. By restricting the claims to the process, the Appellant has given up a significant part of the claims itself and it could not be held to be hit by Section 59 of the Act.”

Contentions of the Respondent

The Respondent made a two-fold argument that:

(1) “product by process claims are primarily product claims and are tested for novelty and inventive step qua the product and not the process. The core of the claim in a product by process patent would only be the product. The Appellant, by removing the product-related claims and converting them into process claims, is changing the very nature of the claims, which is impermissible. Thus, the same ought not to be allowed.”

(2) the original claims were not actually “product by process” rather those were “product” claims only. Hence, converting a “product patent” into a “process patent”, which was not claimed earlier, cannot be allowed as it broadens the scope of the claims.

Observation of the Court

After hearing both the parties, the court observed that the process which is being claimed in the amended set of claims has been explicitly spelled out in the original field detailed description.

In its findings, the court stated that upon perusal of the objections raised in the First Examination Report (FER), the Controller wanted clarification as to whether the scope for which the protection is sought is for a product or for a process. From the amendments, it is evident that the Appellant chose to restrict the patent to the “process” alone, thus narrowing down the scope of its claims. As it is the common understanding that the scope of product claims is broader than the process claims.

Further, the Court referred to the Ayyangar Committee Report, and held that the purport and intention of this Report was to give broader and wider permissibility for amendment of claims and specification prior to the grant and restrict the same post the grant and advertisement thereof. The Report is also categorical in its observation that the invention before and after amendment need not be identical in case of amendment before acceptance ‘so long as the invention is comprehended within the matter disclosed’”.

The Court held that the Report and Section 59, if read together, make it clear that the amendments to a patent specification or claims prior to grant ought to be construed more liberally rather than narrowly. Further, the legislative intent is that no new subject matter should be added to the claims and/or description, which has not been disclosed in the originally filed specification. So long as the invention is disclosed in the specification and the claims are being restricted to the disclosures already made in the specification, the amendment ought not to be rejected, especially, at the stage of examination prior to grant.

The court made its reliance upon the case of AGC Flats Glass Europe SA v. Anand Mahajan[2], which laid down the “Doctrine of Disclaimer” that is, “When the applicant seeks to narrow down or crystalize the claims, ultimately limiting the scope of the invention, the amendment ought to be ordinarily allowed. The only consideration that must be kept in mind is that the amended claims are not inconsistent with the earlier claims in the original specification.”

The same position has been reiterated in the case of, Sulphur Mills Limited v. Dharamraj Crop Guard Limited[3], wherein it was held, “It is usual for patent applicants to edit, amend, modify and vary the claims during the examination and opposition process. So long as the amendments sought are within the scope of the claims originally filed, no adverse conclusion can be drawn on the basis of the said amendments”.

Decision of the Court

With regard to the issue of whether the amendments are allowable which were not claimed at the time of filing of the application under Section 59(1) of the Act, the court held, “the Applicant is amending and narrowing the scope of the claims and not expanding the same. The process sought to be claimed in the amended claims has been clearly disclosed in the patent specification. The said process is not sought to be added newly by way of an amendment. The amendment is, thus, within the scope of the patent specification and claims as originally filed. In the opinion of the Court, the amended claims of the Appellant satisfy the conditions of Section 59(1) of the Act as specified above. Thus, the objection under Section 59(1) of the Act is not sustainable”.


The provision under Section 59(1) of the Act enables the Applicant to make the amendment by way of disclaimer, correction or explanation for incorporating facts. However, the Indian Controllers have been interpreting this section in a very strict manner, wherein they do not allow any new addition or modification to the claims and/or specification, no matter whether the addition and/or modification falls within the scope of the invention.

Before the present case, there had been a number of cases where applications were rejected by the Controller because of the strict interpretation of Section 59(1) of the Act. In the case of Enercon (India) Limited vs. Alloys Wobben, the now defunct IPAB had opined “the correction is going beyond the scope of the claims filed earlier as in the initial claim.”

In another case, Dimminaco A.G. vs. Controller of Patents and Designs, IPAB rejected the proposed amendments stating that “amended claims fall outside the scope of un-amended claims and none of them were disclosed implicitly in the original specification. In other words, amended claims are larger than the original claims.”

Thus, it can be said that even though the provision is clear and the legislative intent behind incorporating such provision, in essence, was to give broader and wider permissibility for amendment of claims and specification prior to the grant, the strict interpretation of Section 59(1) by the Indian Controllers has created a host of issues for the Applicants.


This case law is certainly a very positive step and long-overdue. We believe this case law would eventually result in the change of practice of the Indian Patent Office concerning the acceptance of amendments in claims. As of now, the Controllers interpret the provisions under Section 59 regarding amendments, very strictly. Hopefully, this case law would result in amendments being construed more liberally rather than narrowly.

[1] C.A.(COMM.IPD-PAT)11/2022

[2] 2009(41)PTC 207(Del)

[3] (2021) 87 PTC 567

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