IP Courts Revisiting the Scope of Claims Amendment

After the milestone verdict of the Delhi High Court in Allergan v Controller (2023:DHC:515), now it is time for patent strategists to rejoice over landmark judgments of the Madras High Court, including Starpharma Pty Ltd. v Controller (2023/MHC/4638) that provide similar liberal interpretations of amendment of claims under Section 59 of the Patents Act, 1970.

In prevailing practice at the Indian Patent Office (IPO), the scope of allowability to amend claims is more restricted. While applying Section 59(1), the Controllers strictly forbid amendment of claims where the amended claim does not fall within the textual reading of the pre-amended claims, even if they are disclosed in the complete specification. Let us have a look at the statutory text of Section 59(1):

59. Supplementary provisions as to amendment of application or specification– (1) No amendment of an application for a patent or a complete specification or any document relating thereto shall be made except by way of disclaimer, correction or explanation, and no amendment thereof shall be allowed, except for the purpose of incorporation of actual fact, and no amendment of a complete specification shall be allowed, the effect of which would be that the specification as amended would claim or describe matter not in substance disclosed or shown in the specification before the amendment, or that any claim of the specification as amended would not fall wholly within the scope of a claim of the specification before the amendment.

Purposive interpretation in Allergan

While interpreting the expression “scope of a claim” in Section 59(1), the Delhi High Court held that the claims and complete specification in a patent have to be read together and as a whole. The claims have to be understood in light of the complete specification. They form an integrated whole and cannot be treated as two distinct parts of one document. The High Court further held that the very use of the expression “scope of a claim” in the concluding part of Section 59(1) would require taking into consideration the complete specification of the pre-amended claim and not merely a textually cabined reading of the pre-amended claims themselves, dehors the complete specification.

In this case, the original claims were method claims pertaining to the treatment of an ocular condition. In view of objection under Section 3(i) of the Patents Act, the said method claims were modified into product claims. It was held that the amended claims were in respect of the very same implants for the method of use for which the original claims had been filed. Every detail of the implants, as contained in the amended claims, was, in fact, disclosed in the original claims as filed. The High Court allowed the amendments in which the pre-amended claim was for the method of using certain implants for treating ocular ailments. All details of the said implants were forthcoming in the complete specification in the pre-amended claims. The amendment was only to substitute the method of using the implants with the implants themselves.

Interpretation by Madras High Court

A. Commonwealth case

In Commonwealth Scientific & Industrial Research Org. v Controller (2023/MHC/4501), the Madras HC expounded that Section 59(1) may be divided into three limbs. The first limb contains the overarching limitation that an application for a patent, a complete specification, or any document relating thereto shall not be amended except by way of a disclaimer, correction, or explanation, subject to the further caveat that it shall be permitted only for the purpose of incorporation of an actual fact. The ambit of the first limb is wide and applies to all amendments relating to a patent application, including documents filed in relation thereto. The second limb is focused on amendments to the specification and does not permit amendments that claim or describe matters not in substance disclosed or shown in the specification prior to the amendment. The third limb is focused on the claims in the specification and restricts amendments to those that would fall wholly within the scope of the claims prior to such amendment.

Referring to Allergan, the Madras HC endorsed that “the Delhi High Court interpreted this provision [Section 59(1)] and concluded that the second and third limbs, as described above, should not be interpreted as water-tight compartments. In effect, the Delhi High Court concluded that an application for amendment should be allowed provided the amended claims fall in substance within the scope of the complete specification.” Applying the said interpretation to this case, the Madras HC reversed the Controller’s rejection of amendments and held that it certainly could not be concluded that the amended claims were beyond the scope of the original claims read with the complete specification.

B. Huawei case

In Huawei Technologies v Controller (2023/MHC/4705), the Madras HC held that the second and third limbs are inter-related because every complete specification ends with the claims [Section 10(4)] and again accorded the purposive interpretation of Section 59(1) in Allergan.

C. Starpharma case

The appellant (Starpharma Ltd.) had filed a national phase application (derived from the original PCT application) titled “Method of Treatment or Prophylaxis of Bacterial Vaginosis”. The original claims were in respect of a method of treatment or prophylaxis for bacterial vaginosis, including the administration of a gel formulation. In view of the IPO’s objections, the appellant sought an amendment of the original claims to a gel formulation comprising a dendrimer that inhibits bacterial vaginosis. In the impugned order, the Controller held that the amendment of the claims from “method of treating” to “gel formulation” and other types of claims were not allowable under Section 59(1) as they were beyond the scope of claims originally disclosed. In the original set of claims, there was not a single claim that sought protection for “gel formulation”. The Controller cited the maxim “what is not claimed is disclaimed” and rejected the amended claims.

In the appeal against the Controller’s order before the Madras HC, the appellant relied on Allergan to support its case. The Court examined the original claims, the amended claims, and the complete specification. It was found that (i) the details of the gel formulation as contained in the amended claims were disclosed in the complete specification, and (ii) the structure of an exemplary dendrimer was identical in the amended and original set of claims. The Court held that the request for amendments should not have been rejected when the amended claims were compared with the original claims in light of the disclosures and descriptions contained in the complete specification. Consequently, the Court set aside the Controller’s order and remanded the matter for reconsideration on merits.

Cue from Syngenta

The restrictive nature of amendments is further consolidated when the IPO erroneously invokes the doctrine of “what is not claimed is disclaimed” to reject pre-grant amendments of claims. Starpharma is among such examples where the Controller applied the said “rule” to refuse amendments. Recently, in Syngenta v Controller (2023:DHC:7473-DB), a Division Bench of the Delhi High Court made it clear that the principle of “what is not claimed is disclaimed” may be relevant for infringement analysis, but it has no application to claim drafting. With the exclusion of said doctrine at the pre-grant stage, the interrelation between the second and third limbs of Section 59(1) becomes closer. By extrapolating teachings in Syngenta, the purposive interpretation of claims amendments in Allergan, Commonwealth and Starpharma gets reinforced.


We would like to echo the voice of Allergan – fostering innovations is the very raison d’etre of patent law, to which end any meaningful interpretation of the provisions of the Patents Act must aspire. Placing unduly restricted, pedantic, or hyper-technical interpretations on provisions of the Patents Act in a manner that would discourage innovations would be counter-productive to its purpose. Concurring Allergan, the Madras High Court has also construed the provisions of claim amendments more liberally rather than narrowly. Judicial amity or comity over the purposive interpretation of Section 59(1) would bring the opportunity for patent applicants and practitioners to seek amendments as long as the amended claims fall in substance within the scope of the complete specification. The pre-grant amendments are a process for developing claims before the grant, and therefore, such amendments should not be restricted so that the scope of intended protection is diminished. Ergo, the amended claims should not necessarily be construed as a subset of pre-amended claims. It is not improper for an applicant to broaden its claim as long as the disclosure in the complete specification supports the broadened claims.

Allergan and Starpharma raise procedural concerns as well. In certain cases, the applicant legitimately seeks method of treatment claims in its original international PCT application as patent laws in the US, where it is filed, allow the patenting of such method patents. At the time of entering the National Phase, there could be no occasion for the applicant to amend the claims as originally filed in the PCT application in the US. In such situations, the IPO should also provide adequate opportunity for amendments of claims in terms of the interpretation of Section 59 offered by Allergan and Starpharma.

Based on the judicial decisions discussed above, the IPO should also update its practices and manuals/ guidelines by incorporating relevant ratios and suitable illustrations.