In a well-reasoned judgment issued recently, the Delhi High Court (“Court”) adjudicated upon a suit for patent infringement comprising three patents over insecticides and herbicides.
The three patents owned by the plaintiff relate to a herbicidal composition. The distinctive attribute of the composition developed by the plaintiff is this: it is an amalgam of 2 compounds each of which combats different kinds of weeds. More specifically, the composition consists of a compound called Metsulfuron, which controls grassy weeds and a compound called Sulfosulfuron which controls broad leaf weeds. As a result, the composition, according to the plaintiff, is the only one which effectively tackles grassy as well as broad leaf weeds together.
The composition is in the shape of wettable granules. Around 10% of the composition consists of Metsulfuron and around 70% consists of Sulfosulfuron. The gravamen of the Plaintiff’s case was that it found out from market sources and field executives that the defendant participated in a tender for the supply of a composition consisting of these two compounds roughly in the same proportion in which they are present in the plaintiff’s composition. This being the case, it sued for patent infringement.
To repel the plaintiff’s contentions, the defendant advanced three main arguments.
First, the defendant argued that both compounds comprising the plaintiff’s composition have been well known for a considerable amount of time – metsulfuron methyl since 1986 and sulfosulfuron since the 90s. Many compositions consisting of these compounds have existed for a long time, so the plaintiff’s argument that it invented this composition is lacking in merit. In particular, the defendant relied on a paper published by one Dr. C. P. Singh, at the G.P. Pant College of Agriculture, who dealt with the consequences of a potential combination of these two compounds and patent US 301 which, the defendant argued, relates to a composition containing these two compounds.
Second, the defendant argued that there exist several pertinent differences between the plaintiff’s patent and the defendant’s composition. More specifically, it focused on how, in the defendant’s composition, a stabilizer and the absence of the use of tallow soap as defoamer are missing. Further, the quantity of wetting agents, dispersing agents and suspending agent are significantly higher in the defendant’s composition.
Third, in support of the second argument, the defendant referred to a finding of the Registration Committee of the Central Government Insecticides Board (“Committee”) to the effect that the registration obtained by the defendant for its composition was not covered by the plaintiff’s process patent. In light of the fact that all the three patents of the plaintiff revolve around the same process, the defendant argued, the clear finding that the plaintiff’s process and the defendant’s composition were dissimilar returned by the Committee firmly supported its stance.