TVS Motors preferred an appeal against the earlier Delhi High Court order restraining it from employing the twin spark plug technology upon which Bajaj Auto held patent and non-grant of an injunction against Bajaj from interfering in its manufacture and marketing of its vehicles using the said technology. The Madras High Court in appeal, evaluated upon prima facie case being made out by the parties and noted that TVS had already challenged the validity of Bajaj’s patent by reason of it being taught by Honda patent of 1985. The court added that the applicable approach to a new patent, and one that had been worked for some time differs, as the fact that a patent has been worked for a considerable amount of time without challenge can be adduced as evidence of a prima facie case for its validity.

With regard to infringement and application of doctrine of pith and marrow, the court opined that infringement was determined on the basis of appropriation of the novel features of an invention without the express authority of the proprietor. On the examination of the two patents, the court observed that TVS was employing 3 valves instead of 2, out of which two were intake valves, which permitted the use of that patent with lean and rich air-fuel mixtures. the incorporation of two intake valves provided for the simultaneous swirl and tumble of the fuel charge, which where then evenly ignited by the twin spark plugs. Hence, the court concluded that the combustion engine differed considerably in operation and there was no infringement because different combinations of different elements were employed to generate the same result.

At the same time, it was also the finding of the court that Bajaj’s patent was valid as it represented a technical advance over the Honda patent, which finding, as the court noted, was not binding on the IPAB, should the revocation matter be pursued in that forum by TVS.

Bajaj, however, has approached the Supreme Court where TVS has given an undertaking not to bring the finished product to the market until final determination of the suit.