Delhi High Court reverses Patent refusal, Highlights significance of procedural adherence in handling claims of PCT National phase applications.

The Delhi High Court, in a recent decision dated February 23, 2024, in Mitsui Chemicals Inc. vs Controller of Patents, overturned the patent refusal order issued by the Controller in respect of patent application No. 3877/DELNP/200. This decision underscores the significance of procedural adherence, especially in handling of claims during the national phase entry of PCT applications.


Mitsui Chemicals (the Appellant) filed a PCT national phase application titled “Plant Disease and Insect Damage Control Composition and Plant Disease and Insect Damage Prevention Method” before the Indian Patent Office on June 15, 2009. Subsequently, the application was examined and the Patent Office issued a first examination report (FER), raising objections that the claims of the application fall under “method of agriculture” under Section 3(h), and therefore deemed not allowable.

The Appellant submitted a revised set of claims to address the objections. However, upon review, the patent office was of the opinion that the claims were still non-compliant with Section 3(h) and issued a subsequent examination report. The Appellant responded by submitting amended claims along with Form-13 on May 12, 2014. The Assistant Controller of Patents (the Respondent) refused the application, citing that the amendments made via Form-13 were impermissible under Section 59 of the Act due to a significant shift in the scope of the claims from “A method of preventing plant disease” to an “An insecticidal composition”, essentially transitioning from a process to a product. Additionally, the refusal order maintained the objection under Section 3(h).

The Appellant contested the decision of the Assistant Controller in an appeal, contending that the original claims in the PCT application already pertained to an “insecticidal composition,” contrary to the assertion in the impugned order that the pre-amended claim focused on a “method of treatment of plants.” The Appellant argued that the Controller overlooked the application’s origin as a national phase application based on a PCT filing (bearing application no. PCT/JP2007/072526) and that the amended claims fell within the scope of the original PCT claims. Furthermore, it was highlighted that no formal request for amending the claims was filed when filing the national phase application in India, and the claims on record at that time were the original PCT claims.

The respondent however asserted that the focus of the Appellant’s initial filing in India was on “method of treatment of plant”. They argued that the Appellant had intentionally narrowed down the scope of the claims during the national phase entry by deleting claims 1 and 2, which is permissible under Rule 20 of the Patent Rules, 2003. Since the Appellant chose to delete claims 1 & 2, they cannot reintroduce them through amendments. Consequently, the amended claims pertaining to “insecticidal composition” clearly exceed the scope of the originally filed claims in India.

Claims of the Application

Amended claim

“1. An insecticidal composition, comprising penthiopyrad and dinotefuran as active ingredients, wherein the composition is used for applying the composition to plant seeds or contacting plant seeds with the composition, wherein the content of penthiopyrad is 0.1% to 85% by weight, with respect to the total amount of the composition, and the content of dinotefuran is 0.1% to 85% by weight, with respect to the total amount of the composition.”

Original PCT claims

“1. A plant disease and insect damage control composition comprising active ingredients of: at least one neonicotinoid compound chosen from the group consisting of dinotefuran, clothianidin, nitenpyram, thiamethoxam, imidacloprid, thiacloprid, and acetamiprid; and

(RS)-N-[2-(1,3-dimethylbutyl)thiophene-3-yl]-1-methyl-3-trifluoromethyl-1H-pyrazo le-4-carboxamide (common name: penthiopyrad).

  1. The plant disease and insect damage control composition according to claim 1, wherein the at least one neonicotinoid compound comprises dinotefuran.
  2. A method of preventing plant disease and insect damage, the method comprising applying the composition according to claim 1 or 2 to plant seeds.”

Claim filed at the time of National Phase Entry

“1. A method of preventing plant disease and insect damage, the method comprising applying the composition comprising dinotefuran and penthiopyrad as active ingredients.”

Court’s Findings

The Court observed that since no request for amendment had been made by the Appellant for the PCT claims at the national phase entry, the examination should have been confined to the original PCT claims. The Court noted a critical oversight by the Controller who referenced modified claims from the national phase application instead of the original PCT claims when assessing the scope of the original claims. Stating that the proviso under Rule 20 of the Patents Rules was introduced only in 2016, the provision could not be applied to an application filed before the commencement of the Patent (Amendment) Rules of 2016. The court emphasized that patent applicants are permitted to delete claims at the time of national phase entry and the argument that the Appellant had ‘deleted’ claims 1 and 2 of the PCT claims, and therefore could not reintroduce them, was a misunderstanding by the Controller, of the procedure for amending patent claims during the national phase entry under the Patent Cooperation Treaty (PCT).

In addressing the Respondent’s objection under Section 3(h) of the Patents Act, the Court observed that the impugned order lacked any substantive rationale or analysis to precisely explain why the subject matter of the claims falls within the ambit of Section 3(h) of the Act. Emphasizing the need for a more nuanced and detailed analysis, the Court stressed the importance of scrutinizing whether the claimed invention genuinely constituted a ‘method of agriculture’ or embodied an innovative technical solution to agricultural challenges that might not fall within the exclusions of Section 3(h) of the Act. Consequently, the Court directed the Respondent to re-evaluate the objection, considering the evolving legal landscape and judicial interpretations, particularly considering the significant judgment by the High Court of Calcutta in Decco Worldwide Post Harvest Holdings B. V & Anr. v. The Controller of Patents and Designs & Anr.


In light of the aforementioned observations, the Court set aside the impugned order and remanded the matter to the Controller for de novo consideration. The Court also directed the Patent Office to issue a fresh hearing notice clearly delineating all the objections and to render a decision within three months from the date of conclusion of hearing.

Citation: Mitsui Chemicals Inc vs Controller Of Patents, Delhi High Court, 23rd February, 2024, C.A.(COMM.IPD-PAT) 196/2022

Authored by Neetha Mohan, Patents Team, BananaIP Counsels


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