If the thing rests in speculation or experiment; if the process pursued for its development has failed to reach the point of consummation, it cannot avail to defeat a patent founded upon a discovery or invention which was completed. Because in the other case there was only progress, however near that progress may have approximated to the end in view. The law requires not conjecture, but certainty.
Complainant, a patent owner sought to enjoin the defendants from infringing the patent. The patent is for a door lock with a latch reversible, so that the lock can be applied to doors opening either to the right or the left hand. The patent originally belonged to Charles R. Miller until it was eventually assigned to the complainant. No question was raised as to the complainant's title, nor as to the alleged infringement by the defendants. The answer alleges that the thing patented, or a material and substantial part thereof, had been, prior to the supposed invention thereof been known and used before; that a certain Barthol Erbe, a Birmingham resident, was the prior inventor. They insist that Erbe had priority and this was fatal to the patent.
Is the patent invalid by anticipation under Patent Act of 1836?
The court held that burden of proof rested upon the defendants to prove prior invention. Further, in making that proof, every reasonable doubt was to be resolved against appellees. If prior invention was embryonic, inchoate, rested on speculation or experiment, or the process pursued for its development had failed to reach the point of consummation, the invention could not defeat the patent of an invention or discovery already completed. The court held that, in applying those severe standards, complainant’s patent was invalid for anticipation under Patent Act of 1836 § 6. A prior invention, anticipating that of appellant's, was complete and working, known to at least five other persons, put into use, tested, and shown to be successful prior to the grant of appellant's patent.