Recently, the Madras High Court in TVS Motor Company Limited vs The Assistant Controller of Patents and Designs [C.M.A.(PT). No.42 of 2024, decided dated June 5, 2025], reiterated the standards required in an obviousness analysis under patent law. The Court held that when examining whether an invention is obvious, it is not enough for the Patent Office to extract certain features from cited prior art documents and state that they overlap with the claimed invention. Instead, the authority must consider whether the prior arts contain any direct or indirect teaching, suggestion, or motivation that would lead a person skilled in the art (PSITA) to arrive at the invention. In the absence of such reasoning, a refusal of a patent application cannot be sustained.

The instant appeal arose from the rejection of patent application number 798/CHE/2011, entitled “An Internal Combustion Engine”. The subject application claimed a specific improvement in the bearing structure of an internal combustion engine, intended to reduce or eliminate the rattling sound caused by backlash between the bearing race and the crankcase. The application contained one independent claim and two dependent claims. The independent claim, framed in two-part form, described a bearing structure for supporting a crankshaft comprising an engaging groove for receiving a tapered circlip, which presses against a washer deployed between the bearing and the circlip and which exerts continuous pressure on the bearing thereby controlling the bearing float. The crux of the invention was that by this configuration, the backlash between the bearing race and the crankcase, which otherwise produced undesirable rattling noise, could be absorbed and reduced.

The Controller rejected the application on the ground of lack of inventive step. The objection taken by the Controller was essentially twofold:

• By referring to the extracts of the cited prior art documents D1 and D2, the Controller concluded that D1 disclosed a circlip, and D2 disclosed a restraining clamp that controls backlash. On this basis, he reasoned that the claimed invention was not inventive, since both features were already known in the art.
• It was held that the applicant had failed to disclose clearly whether the claimed invention was intended to reduce axial movement (which is something D2 was directed towards) or rotational movement and pressure. In the Controller’s view, this lack of clarity undermined the technical contribution of the invention.

The Appellant contested this reasoning before the Court and asserted that document D1 was not analogous to the claimed invention, since D1 was directed at securing the bearing cap relative to the shaft and bearing body, and not at preventing rattling sounds caused by backlash like the claimed invention. It was further pointed out that D1 related to a diesel engine and was therefore not relevant. As for D2, the Appellant argued that it attempted to reduce axial movement through the use of a clamp, which was technically different from a circlip. The Appellant emphasized that neither D1 nor D2 contained any teaching, suggestion, or motivation that would lead a PSITA to arrive at the claimed invention.

After analysing the claimed invention and the cited prior arts documents, the Court noted that the complete specification of the subject application explicitly identified the technical problem as the “backlash” between the outer race of the bearing and the crankcase, which created rattling noise during engine operation. The inventive solution was to introduce a tapered circlip pressing against a washer, exerting continuous pressure to stabilize the bearing. In contrast, document D1 was concerned with securing the bearing cap and applying pre-stressing pressure on the bearing shells, without any reference to backlash or rattling. The Court observed that simply because D1 used a circlip, it could not be concluded that the claimed invention would be obvious in view of D1. Prior art D2, though addressing the problem of rattling sound, proposed a different mechanism involving clamps to reduce axial movement, and therefore differed materially from the claimed invention.

The Court reprimanded the Controller’s approach of rejecting the application by merely citing that one prior art used a circlip and the other addressed backlash, while simultaneously recording that the clarity about whether the claimed invention was directed at reducing axial or rotational movement was absent. The Court stressed that “while conducting an obviousness analysis it is necessary to examine whether the cited prior arts contain either direct or indirect pointers which would lead a person skilled in the art to the claimed invention”.

The decision reiterates that obviousness analysis cannot rest on cursory parallels between prior art and the claimed invention. It must involve a structured and reasoned analysis.

The matter was accordingly remanded to the Patent Office for reconsideration.