shall be used in violation of the license. To that extent competition in the sale of such articles, for use with the machine, will be affected; for sale to such users for infringing purposes will constitute contributory infringement. But the same consequence results from the sale of any article to one who proposes to associate it with other articles to infringe a patent, when such purpose is known to the seller. But could it be said that the doctrine of contributory infringement operates to extend the monopoly of the patent over subjects not within it because one subjects himself to the penalties of the law when he sells unpatented things for an infringing use? If a patentee says, "I may suppress my patent if I will. I may make and have made devices under my patent, but I will neither sell nor permit anyone to use the patented things," he is within his right, and none can complain. But if he says, "I will sell with the right to use only with other things proper for using with the machines, and I will sell at the actual cost of the machines to me, provided you will agree to use only such articles as are made by me in connection therewith," if he chooses to take his profit in this way, instead of taking it by a higher price for the machines, has he exceeded his exclusive right to make, sell and use his patented machines? The market for the sale of such articles to the users of his machine, which, by such a condition, he takes to himself, was a market which he alone created by the making and selling of a new invention. Had he kept his invention to himself, no ink could have been sold by others for use upon machines embodying that invention. By selling it subject to the restriction he took nothing from others and in no wise restricted their legitimate market.

A like objection has been made against injunctions restraining the sale for infringing purposes of a single element in a patent combination. It was said that to enjoin such sales, although the thing sold was intended

to be used with other elements to complete an infringing combination, was to extend the scope of the patent so as to give to the patentee the same advantage as if the element had been claimed alone. But in Davis Electrical Co. v. Edison Co., 60 Fed. Rep. 276, 280, Judge Putnam answered this, saying:

"Neither in such instances, nor in the case at bar, is the course of the law to be turned aside because the practical result may be to give a patentee for the time being more than the patent office contemplated, nor is the patentee to be deprived of his just rights because under some circumstances he gets incidental advantages beyond what he expressly bargained for. We do not in terms give the patentee the benefit of a claim for the filament alone, nor prohibit its use in some other combination than that set out in the second claim, if some ingenious way of making such other combination is ever discovered."

In Thomson-Houston Co. v. Kelsey Co., 72 Fed. Rep. 1016, the language was adopted by Judge Townsend.

Neither can we see that the liability of the defendants for aiding and abetting an infringing use by Miss Skou would be different whether she had made her machine in open defiance of the rights of the patentee or had bought it under conditions limiting her right of use. If she had made it, she would have been liable to an action for infringement for making; and if she used it, she would become liable for such infringing use. But if the defendants knew of the patent and that she had unlawfully made the patented article, and then sold her ink or other supplies without which she could not operate the machine, with the intent and purpose that she should use the infringing article by means of the ink supplied by them, they would assist in her infringing use.

66

'Contributory infringement," says Judge Townsend in Thomson-Houston Co. v. Kelsey Co., 72 Fed. Rep. 1016, VOL. CCXXIV-3

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1017, "has been well defined as the intentional aiding of one person by another in the unlawful making or selling or using of the patented invention." To the same effect are Wallace v. Holmes, 29 Fed. Cases, 74, 79; Risdon Iron & Locomotive Works v. Trent, 92 Fed. Rep. 375; ThomsonHouston Co. v. Ohio Brass Works, 80 Fed. Rep. 712; American Graphophone Co. v. Hawthorne, 92 Fed. Rep. 516.

In the Risdon Case, a member of the firm which made the plans for the construction of certain mining machinery to be made in the owner's shop, and then superintended its erection at the mine, was held to be guilty of infringement, though he neither personally made nor used the machines which were found to be an infringement of valid patents. In American Graphophone Co. v. Hawthorne, one who sold a machine with knowledge that it was to be used to produce an infringing article was held to be liable as an infringer.

For the purpose of testing the consequence of a ruling which will support the lawfulness of a sale of a patented machine for use only in connection with supplies necessary for its operation bought from the patentee, many fanciful suggestions of conditions which might be imposed by a patentee have been pressed upon us. Thus it is said that a patentee of a coffee pot might sell on condition that it be used only with coffee bought from him, or, if the article be a circular saw, that it might be sold on condition that it be used only in sawing logs procured from him. These and other illustrations are used to indicate that this method of marketing a patented article may be carried to such an extent as to inconvenience the public and involve innocent people in unwitting infringements. But these illustrations all fail of their purpose, because the public is always free to take or refuse the patented article on the terms imposed. If they be too onerous or not in keeping with the benefits, the patented article will not find a market. The public, by permitting the invention to go unused, loses nothing

which it had before, and when the patent expires will be free to use the invention without compensation or restriction. This was pointed out in the Paper Bag Case, where the inventor would neither use himself nor allow others to use, and yet was held entitled to restrain infringement, because he had the exclusive right to keep all others from using during the life of the patent. This larger right embraces the lesser of permitting others to use upon such terms as the patentee chooses to prescribe. It must not be forgotten that we are dealing with a constitutional and statutory monopoly. An attack upon the rights under a patent because it secures a monopoly to make, to sell and to use, is an attack upon the whole patent system. We are not at liberty to say that the Constitution has unwisely provided for granting a monopolistic right to inventors, or that Congress has unwisely failed to impose limitations upon the inventor's exclusive right of use. And if it be that the ingenuity of patentees in devising ways in which to reap the benefit of their discoveries requires to be restrained, Congress alone has the power to determine what restraints shall be imposed. As the law now stands it contains none, and the duty which rests upon this and upon every other court is to expound the law as it is written. Arguments based upon suggestions of public policy not recognized in the patent laws are not relevant. The field to which we are invited by such arguments is legislative, not judicial. The decisions of this court, as we have construed them, do not so limit the privilege of the patentee, and we could not so restrict a patent grant without overruling the long line of judicial decisions from Circuit Courts and Circuit Courts of Appeal, heretofore cited, thus inflicting disastrous results upon individuals who have made large investments in reliance upon them.

The conclusion we reach is that there is no difference, in principle, between a sale subject to specific restrictions as to the time, place or purpose of use and restrictions

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requiring a use only with other things necessary to the use of the patented article purchased from the patentee. If the violation of the one kind is an infringement, the other is also. That a violation of any such restriction annexed to a sale by one with notice constitutes an infringing use has been decided by a great majority of the Circuit Courts and Circuit Courts of Appeal, and has come to be a wellrecognized principle in the patent law, in accordance with which vast transactions in respect to patented articles have been conducted. But it is now said that the numerous decisions by the lower courts have been erroneous in respect to the proper construction of the limit of the monopoly conferred by a patent, and that they should now be overruled. To these courts has been committed the duty of interpreting and administering the patent law. There is no power in this court to review their judgments, except upon a writ of certiorari, or to direct their decisions, save through a certified interrogatory for direction upon a question of law. This power to review by certiorari is one which has been seldom exercised in patent cases. A line of decisions, which has come to be something like a rule of property, under which large businesses have been conducted, should at least not be overruled except upon reasons so clear as to make any other construction of the patent law inadmissible.

The earliest of the reported cases in which the precise question here presented arose were cases arising in suits for the infringement of a patent upon an iron band connected by a buckle, intended for binding cotton bales. The band and this buckle were of iron. The buckle was so adjusted as that the band could be removed from the bale only by cutting. Upon the buckle were stamped the words: "Licensed to use only once." When cut from the bale the band and buckle were sold to persons, who used the buckles either upon a new band, or one repaired, and these bands were sold to planters to be used again in baling