Hotchkiss v. Greenwood, 52 U.S. 11 (1850)
A patent granted for a "new and useful improvement in making door and other knobs of all kinds of clay used in pottery, and of porcelain" by having the
"cavity in which the screw or shank is inserted by which they are fastened largest at the bottom of its depth, in form of a dovetail, and a screw formed therein by pouring in metal in a fused state"
District Court rules patent invalid: Appellate upholds ruling
Ruled invalid: did not invent anything new, just took previous inventions and put them together. The only thing not previously in use was the using of that specific method of that specific material for that specific use in that specific shape.
The test was that if no more ingenuity and skill was necessary to construct the new knob than was possessed by an ordinary mechanic acquainted with the business, the patent was void, and this was a proper question for the jury.
"The plaintiffs prayed the court to instruct the jury that, although the clay knob, in the form in which it was patented, may have been before known and used, and also the shank and spindle by which it is attached may have been before known and used, yet if such shank and spindle had never before been attached in this mode to a knob of potter's clay, and it required skill and invention to attach the same to a knob of this description, so that they would be firmly united, and make a strong and substantial article, and which, when thus made, would become an article much better and cheaper than the knobs made of metal or other materials, the patent was valid."
The instruction assumes, and, as was admitted on the argument, properly assumes, that knobs of metal, wood &c., connected with a shank and spindle, in the mode and by the means used by the patentees in their manufacture, had been before known, and were in public use at the date of the patent, and hence the only novelty which could be claimed on their part was the adaptation of this old contrivance to knobs of potter's clay or porcelain; in other words, the novelty consisted in the substitution of the clay knob in the place of one made of metal or wood, as the case might be. And in order to appreciate still more clearly the extent of the novelty claimed, it is proper to add, that this knob of potter's clay is not new, and therefore constitutes no part of the discovery
It may afford evidence of judgment and skill in the selection and adaptation of the materials in the manufacture of the instrument for the purposes intended, but nothing more.
Justice Woodbury dissented
Then, if they became convinced that the knob in this case, by its material, or form inside, or combination with the shank, was in truth better and cheaper than what had preceded it for this purpose, it would surely be an improvement. It would be neither frivolous nor useless, and under all the circumstances it is manifest that the skill necessary to construct it, on which both the court below and the Court here rely, is an immaterial inquiry, or it is entirely subordinate to the question whether the invention was not cheaper and better. Thus, some valuable discoveries are accidental, rather than the result of much ingenuity, and some happy ones are made without the exercise of great skill, which are still in themselves both novel and useful. Such are entitled to protection by a patent, because they improve or increase the power, convenience, and wealth of the community.
Earle v. Sawyer, 4 Mason 1
a combination, if simple and obvious, yet if entirely new, is patentable. And it is no objection to it, that up to a certain point it makes use of old machinery.