44 HARVARD LAW REVIEW.
- 'This testimony stands uncontradicted, except by the suggestion of
defendant's counsel of possible uses to which such shade-holders might be applied." Wallace v. Holmes was followed, and was quoted at some length with unqualified approval. Many cases under the rule of contributory infringement have been decided by the Federal courts, and are in harmony with those herein discussed. In one case the facts raised the discussion of the rule in all its shades of application ; but, after all the questions arising from a quite complex situation had been sifted and disposed of, the case called for the unqualified application of the rule. This was Heaton Peninsular Button Fastener Company v. Eureka Spe- cialty Company,^ contested on bill and demurrer. Later cases are Thomson-Houston Electric Co. v. H. W. Johns Co. ; ^ Thomson- Houston Electric Co. v. Ohio Brass Co.^ The formulation of a rule is not a task which the writer under- takes with confidence ; it is submitted, however, that the rule to be deduced from the cases under discussion is not too broadly stated thus : — Any act done with intent to contribute to an infringement of patent-rights is wrongful, tantamount to a direct infringement, and will be enjoined by a court of equity, although in itself, and con- sidered apart from its intended purpose, such an act might, be lawful. In its enforcement, this rule will be guarded by such terms of application as will prevent it from embarrassing the person enjoined in the performance of the acts in question when properlydissociated from any wrongful intent. Odin B. Roberts. 1 47 U. S. App. 146. a 78 Fed. Rep. 364. » 80 Fed. Rep. 712.
