The opinion of the court was delivered by: ATWELL
Plaintiff alleges the ownership of letters patent No. 2,541,637, issued February 13, 1951, for, 'Method of Vaporizing Lindane in Ventilated Rooms.'
Generally, the complainant alleges that defendant Cauthorn is the infringer, and that the others are contributory infringers.
The defendants deny generally, and, particularly, infringement and contributory infringers.
Patent relates to the evaporation, or, vaporization, and/or sublimation of Lindane in rooms at a rate to provide a concentration that will kill flies and other insects that remain in the room for a sufficient period. That such evaporation in ventilated rooms will not attain a concentration harmful to food, or human occupants.
Once again we turn our attention to fundamentals for guiding posts in the preparation of a decree.
(a) Issuance of a patent is prima facie evidence of novelty and utility.
(b) In infringement cases, the burden rests on the plaintiff to establish infringement, but the burden is on the defendant to demonstrate illegality of patent claims.
(c) In an infringement case, reasonable doubt must be resolved in favor of the claim for which the patent was issued.
(d) Under the statute, a patentable device must not only be new and useful, but must also be an invention, or, discovery.
(e) The commercial success of the patented article cannot be relied upon to show validity of an otherwise invalid patent. It can only be relied upon where the question of patentability is in doubt.
(f) The language used in specifications and claims of a patent must be construed in accordance with its plain, ...