INFRINGEMENT OF PATENT RIGHTS. 37 Wallace v. Holmes were enjoined, notwithstanding that the thing which they manufactured and sold did not in itself embody the invention secured to the complainants. The act was found to be wrongful because of the obvious intent of the defendants to make the burner for use only with another thing which the user was to supply. If this were the only case on the subject of con- tributory infringement it might perhaps be argued that the incom- pleteness of the burner as made by the defendant offered the key to the rule to be applied ; but this can only be regarded as one of several grounds for inferring intent, which made the act of manu- facture and sale wrongful. The infringement of patent rights is a tort; here there is an instance where the intent of a factor makes an act which in itself is innocent, a tort The writer is aware that a vexed question which has been thoroughly discussed in these columns ^ is suggested by the state- ment of the result of Wallace v. Holmes ; but it is not the present purpose to attempt a reopening of the question. Wallace v. Holmes has been followed and the application of its principle ex- tended in patent cases, so that, whether the case and its successors are regarded as the extension of a sound doctrine or the contrary, it must be conceded that the principle of the case is established in the patent law at least, and that contributory infringement will be treated in the Federal courts with the same remedies as are appli- cable to cases of direct infringement. In Wallace v. Holmes the specific state of facts might, if the case stood alone, give ground for asserting that the rule there applied went only so far as to hold that the defendant, who was proved to have made a thing useless by itself, might be presumed to be a party to the operative completion of the infringing com- bination, and that only where such a presumption proved inevi- table should there be a suspension of, or rather an exception to, the rule which permits a patentee to control or suppress only full embodiments of his claim. On this theory, however, difficulty would arise for want of parties. The question of joint infringe- ment is distinct from that of contributory infringement, and if the collusive circumstances of joint infringement were regarded as the key to the situation, then in the absence of actual conspiracy between several persons, who by successive individual acts com- plete the embodiment of infringement, no recovery or relief could 1 Lumley v. Gye, Harvard Law Review, ii. 19.
