The Delhi High Court, in Crystal Crop Protection Limited Sudpita Dey, Assistant Controller of Patents & Ors. [C.A.(COMM.IPD-PAT) 86/2022; decision dated April 4, 2026], dismissed an appeal challenging the refusal of patent application number 1607/DEL/2010 relating to an insecticidal composition comprising Fipronil (3.5% w/w) and Emamectin Benzoate (1.5% w/w) in a suspension concentrate (SC) formulation. A key feature of the subject invention was the alleged synergistic interaction between the two active ingredients, resulting in enhanced insecticidal activity.

The Controller refused the patent application, accepting the grounds raised in the pre-grant opposition viz lack of novelty, lack of inventive step, and non-patentability under Section 3(d). Before the Court, the Appellant argued that the impugned order lacked reasoning and merely reproduced the opponent’s submissions, failed to independently analyse the cited prior art and incorrectly treated the SC formulation as the inventive feature while ignoring the claimed synergistic effect.

The Court rejected these contentions. It held that the impugned order reflected adequate consideration of the cited prior art and the parties’ submissions. After conducting a detailed examination of the cited prior art documents, the Court found that the claimed invention did lack novelty and inventive step. It noted that while the argument that the Controller had merely copy-pasted the objections raised by the pre-grant opponents may appear “superficially attractive”, it was unfounded and untenable when viewed against the Controller’s detailed analysis of the objection of lack of inventive step.

On the merits, the Court observed that the cited prior art, particularly CN’627 and CN’546, disclosed the claimed combination of Fipronil (3.5% w/w) and Emamectin Benzoate (1.5% w/w) through their specific examples and embodiments. It was not persuaded by the Appellant’s attempt to distinguish the references on the basis of formulation type or the presence of synergists, observing that the prior art already disclosed the relevant active ingredients in the claimed concentrations and also contemplated suspension formulations. Accordingly, the Court found no error in the Controller’s conclusion that the essential features of the claimed composition were already disclosed in the prior art, and, therefore, upheld the finding of lack of novelty.

Further, it held that the prior art sufficiently disclosed similar compositions and that a person skilled in the art would have been able to arrive at the claimed composition without exercising inventive ingenuity.

Addressing the allegation of impermissible mosaicing, the Court relied on Sterlite Technologies Ltd. v. HFCL Ltd., reiterating that combining multiple prior art documents does not amount to impermissible mosaicing where the documents relate to substantially similar products and collectively represent the existing state of the art. In such circumstances, their combined consideration is permissible while assessing inventive step.

The Court also reiterated the principles governing assessment of inventive step laid down in Agriboard International LLC vs. Deputy Controller, observing that the Controller must examine (i) the invention disclosed in the prior art, (ii) the invention claimed in the application, and (iii) the manner in which the claimed invention would be obvious to a person skilled in the art. While reaffirming this requirement, the Court found that the present case satisfied that standard and that the claimed invention lacked inventive step in view of the cited prior art.

Having upheld the refusal on the ground of lack of inventive step under Section 25(1)(b) and Section 25(1)(e), the Court did not find it necessary to examine the objections relating to Section 25(1)(g) read with Section 3(d).

Accordingly, the appeal was dismissed and the refusal of the patent application was affirmed.