An appeal was filed by The Nippon Signal Co., Ltd. under Section 117A of the Patents Act, 1970, against the Controller’s order rejecting the grant of a patent for an invention titled “Redundant Control Device and System Switching Method”. The application was refused under Section 15 on the ground that the claimed invention lacked inventive step in view of prior art documents D1 and D2. In The Nippon Signal Co., Ltd. vs Assistant Controller of Patents and Designs [C.A.(COMM.IPD-PAT) 84/2024], decided on May 29, 2026, the Delhi High Court examined whether the Controller had adequately considered the appellant’s response to the First Examination Report and the post-hearing written submissions before refusing the application.
Appellant’s Case for Remand
The appellant pointed out that the respondent Controller had failed to consider the detailed submissions made in response to the First Examination Report and the post-hearing written submissions, as also the fact that the claims had been amended to address the objections raised in the FER and the hearing notice. The appellant submitted that the respondent Controller had not considered the differences brought out by the appellant, which, if considered, would have demonstrated that a person skilled in the art could not have been motivated by the teachings of D1 and D2 to arrive at the claimed invention. The appellant relied on Boehringer Ingelheim Vetmedica GMBH vs Controller of Patents [2024 SCC OnLine Del 8578], wherein it was held that non-consideration of written submissions was sufficient reason to remand the matter to the Controller. The appellant argued that, on this ground alone, the impugned order was untenable in law.
The appellant submitted that it had brought to the respondent Controller’s attention that D1 disclosed a duplexed system for an operation processor, but did not specify that it related to trains. Explaining the claimed invention, the appellant submitted that it related to a redundant control device used for a train controller. The advantageous effects disclosed in the description were that the two dual on-board controllers could be reduced by half, thereby saving costs, and that the switching period could be shortened, resulting in reduced signal transmission time during switchover. This would assist in executing precise train control; for example, the interval between trains could be reduced to enhance operational efficiency. The appellant contended that these advantages were specific to the use of the device in a train controller and could not be conceived from D1. Therefore, reliance on D1 by the respondent was wholly misplaced.
Respondent Controller’s Reply
The respondent Controller maintained that the invention lacked inventive step, as the teachings of cited prior arts D1 and D2, whether taken alone or in combination, fully disclosed, suggested and taught the claimed invention. The respondent argued that the purported advantages, such as faster switchover and cost-effectiveness, were expected and inherent results of implementing known redundant control or duplexing system techniques and were not inventive. The respondent further submitted that a detailed obviousness analysis had been carried out in accordance with the law laid down by the Supreme Court in Biswanath Prasad Radhey Shyam vs Hindustan Metal Industries [(1979) 2 SCC 511]. In this case, it was held that obvious variations of known technology do not constitute an invention.
The respondent submitted that obvious variations of known technology do not constitute an invention. It was contended that although the appellant had pointed out differences in the prior arts, particularly that D1 did not specify its application to trains, the technology employed in the claimed invention, namely, duplexing for system reliability, was widely known in control systems and electronic devices. Therefore, the mere use of the device in a train control system did not constitute an invention and, at the highest, amounted to an application of known technology.
Appellant’s Rejoinder
In rejoinder, the appellant submitted that the mere fact that the claimed invention and D1 and D2 fell within the broad domain of redundant duplex control systems did not negate inventive step. Relying on Avery Dennison Corporation vs Controller of Patents and Designs [2022 SCC OnLine Del 3659], wherein it was held that simplicity does not defeat patentability, the appellant contended that although adapting duplex control to trains was alleged to be a routine field-of-use choice, the placement and interconnection of the components in the claimed invention were not conventional.
The appellant pointed out that inventive step must be assessed holistically and not by dissecting individual components. Relying on the Calcutta High Court’s ruling in Groz-Beckert KG vs Union of India [MANU/WB/0140/2023], wherein it was held that obviousness cannot be established merely by isolating individual known parts, the appellant argued that D1 and D2 neither taught nor suggested the placement of controllers in separate train cars with a dedicated synchronisation line ensuring phase alignment without handshake latency. The appellant submitted that if the respondent’s argument that obvious variations of known technology do not constitute an invention were accepted without considering the claimed combination as a whole, no invention comprising a combination of known techniques would qualify for patent protection.
Court’s Analysis and Findings
The Court perused the impugned order and the complete specification and found that the bi-directional and reversible switchover of the subject invention was not taught or suggested by D1’s permanent, one-way failover structure. Similar differences had been highlighted with respect to D2, but there was no consideration or even mention of them in the impugned order. The Court observed that although it was the respondent’s prerogative and within its expertise to decide whether a claimed invention involved an inventive step, the decision had to be reasoned and based on material facts and scientific reasoning. The respondent was under an obligation to consider and analyse all relevant points raised by the applicant before passing an order.
Agreeing with the appellant’s submissions, the Court found that the respondent had failed to consider the detailed submissions made in response to the FER and in the post-hearing written submissions, as also the fact that the claims had been amended to address the objections raised in the FER and the hearing notice. The appellant had provided a detailed analysis in the written submissions explaining why reliance on prior arts D1 and D2 was incorrect. However, the respondent continued to rely on the objections raised without considering the differences brought forth by the appellant. Referring to the decision in Boehringer Ingelheim, wherein non-consideration of written submissions was held to be sufficient reason for remand, the Court found that the present matter was a fit case for fresh consideration by the respondent.
Decision of the Court
Allowing the appeal in part, the Court quashed and set aside the impugned order and remanded the matter to the Patent Office for fresh consideration. The respondent was directed to consider the patent application afresh, taking into account the submissions made by the appellant in response to the FER, the post-hearing written submissions and the appeal. The Court further directed that the determination of inventive step be carried out in accordance with the applicable law and that a decision be taken within four months after granting the appellant an opportunity of hearing.
Conclusion
The Court highlighted that the Patent Office is under an obligation to consider and analyse all relevant points raised by an applicant before passing a reasoned order. Failure to consider material submissions, particularly detailed responses to the FER and post-hearing written submissions, may constitute sufficient reason to set aside the refusal order and remand the matter for fresh consideration. Following the ruling in Boehringer Ingelheim, the Court held that non-consideration of written submissions justified remand of the matter to the Controller. The decision also reiterates that determination of inventive step must be based on material facts, scientific reasoning and proper consideration of the differences between the claimed invention and the cited prior arts.
Author: DPS Parmar