o be patented, must be applied for by the actual
inventor, and in the absence of acts constituting a transfer, the
patent, and all legal ownership in it, and all rights under it, go
exclusively to the inventor. In the absence of express or implied
contract, a mere employer of the inventor has no rights under the
patent. Only contracts or assignments give to the employer, or to
anyone else, a license or a partial or entire ownership in the patent.
The equity of this may be appreciated by examples. A journeyman
carpenter invents an improvement in chronometer escapements and
patents it. The man who owns the carpenter shop has no shadow of claim
on or under this patent. Again, the carpenter invents and patents an
improvement in jack planes. The shop owner has no rights in or under
the patent. Again, the carpenter invents an improvement in window
frames, and the shop owner has no rights. He has no right even to make
the patented window frame without license. The shop owner, in merely
employing the carpenter, acquires no rights to the carpenter's
patented inventions. But there are cases in which an implied license
would go to the shop owner. For instance, if the carpenter was
employed on the mutual understanding that he was particularly
ingenious in devising carpenter work, and capable of improving upon
the products of the shop; and if in the course of his work he devised
a new and patentable window frame, and developed it in connection with
his employment and at the expense of his employer; and if the new
frames were made by the employer without protest from the carpenter,
the carpenter could, of course, patent the new frame, but he could not
oust the employer in his right to continue making the invention, for
it would be held that the employer had acquired an implied license.

If he could not use it, then he would not be getting the very
advantage for which he employed this particular carpenter, and if he
did get that right, he would be getting all that he employed the
carpenter for, and that right would not be at all lessened by the fact
that the carpenter had a patent under which he could license other
people. The patent does not constitute the right to make or use or
sell, for such right is enjoyed without a patent. The patent
constitutes the "exclusive" right to make, sell or use, and this the
shop owner does not get unless he specially bargains for it. Implied
licenses stand on delicate ground, and where men employ peo