In AbbVie Ireland Unlimited Company vs Deputy Controller of Patents and Designs [C.A.(COMM.IPD-PAT) 65/2024, decided on 29 April 2026], the Delhi High Court set aside the Controller’s refusal of divisional patent application number 201918048639 relating to the process for preparing an intermediate compound of formula (C) used in preparation of compound of formula (A1), and remanded the matter for fresh consideration.

The Controller had refused the divisional application on two grounds: first, that the claims were not maintainable under Section 16 because they had already been granted in the parent application; and second, that the claimed invention lacked an inventive step under Section 2(1)(ja) in view of prior art documents D1-D4.

Before the Court, AbbVie contended that the Controller had erred in holding the divisional application to be non-maintainable since it had been filed in response to a lack of unity objection raised during the prosecution of the parent application (8479/DELNP/2015). It was further pointed out that the divisional application was directed towards a distinct invention relating to the preparation of an intermediate compound, whereas the parent patent concerned preparation of formula A1, the final product.

With respect to inventive step, AbbVie argued that the impugned order failed to provide any substantive reasoning explaining how the cited prior art documents rendered the claimed invention obvious. It was argued that the Controller had neither engaged with nor addressed its submissions distinguishing the claimed invention from the cited prior art. The Controller merely reproduced portions from the prior art documents and, without any analysis, concluded that the claimed invention lacked an inventive step.

In response, the Controller argued that the divisional application was refused on merits alone and not on the issue of maintainability. However, the Court noted that the impugned order expressly rejected the divisional application on the grounds of both maintainability under Section 16 and lack of inventive step.

The Court noted that the finding on maintainability was contained in a single conclusory paragraph without any substantive analysis of the Applicant’s arguments regarding the distinction between the parent and divisional claims. The Court emphasised that reasoned orders are indispensable.

Significantly, the Court held that where a divisional application is filed pursuant to an objection raised by the Patent Office itself, it would be impermissible for the Controller to subsequently reject the application on the ground that the divisional claims were already covered by the parent application. Referencing prior IPAB decisions, the Court found the Controller’s conclusion on non-maintainability to be unsustainable.

On inventive step, the Court noted that although the Controller had prepared comparative tables between the claimed invention and the prior art references, the impugned order merely concluded that the invention was obvious without any analysis. The Court found that the Applicant’s detailed submissions concerning the technical differences between the claimed process and prior art documents had not been adequately considered.

The Court underscored that refusal of a patent application is a serious matter that may deprive an applicant of the fruits of years of research and could potentially result in meritorious inventions being lost.

Accordingly, the Court set aside the impugned order and remanded the matter to the Patent Office for fresh consideration after considering the Applicant’s submissions on inventive step.