An article of manufacture is not patentable because means have been devised to make it more perfectly than before; it must be new in itself and not merely in its workmanship. A machine-made article therefore is not patentable simply because it is thus made, and no longer by hand.
The substitution of an art, manufacture, or composition of matter of one element or device for another which does the same thing in the same way and accomplishes a similar result is not invention. Even if the substituted part performs the function better, there is no patentable invention unless some new function or result is secured. Changes therefore of the relative location of parts without changing the functions performed by them are not an invention, nor is the omission of a part with a corresponding omission of function.
A patent can issue only to the inventor, or if he is dead to his executor or administrator. If there be two original inventors the one who first made it or brought it to this country is entitled to a patent. A patent granted on the application of a non-inventor is void. By first inventor is meant the one who first had a mental conception of the invention provided he exercised diligence in perfecting it. If there be a rival claimant the party who first reduced to practice the invention was, until the contrary fact is shown, the first inventor. One who merely utilizes the ideas of others is not an original inventor and is not entitled to a patent. In the United States any person, regardless of residence, citizenship or age may obtain a patent.
An invention is reduced to practice when it is so far perfected that it may be put into practical and successful use. The machine may not be perfectly constructed, but it embodies all the essential elements of the invention. Demonstration of its success by actual use is usually necessary, but not always. The reduction to practice must be by the applicant for a patent, or by his agent; to do this by a third party will not suffice. The person who first conceived the invention, but was later than his rival in reducing it to practice, is not regarded as the first inventor unless he exercised due diligence to perfect his invention after the time that his rival entered the field against him.