502. Combination patents.

A combination or collocation of integers the production of which has required independent thought, ingenuity or skill may constitute good subject matter for the grant of a patent, provided that it enables a more efficient result to be obtained, even though all the integers are old1. This general statement covers two classes of invention:

  1.  

    (1)     combinations proper, in which the several integers are so placed together that by their working interrelation they produce a new or improved result2, so that the combination is more than the mere sum of its integers