final product actually contains all or part of the patented product. Where the patented product can actually be identified in the product sold into Canada, there may be a strong case for a finding of infringement. The stage at which the patented product or process is used. For example, use of a process as a preliminary step of a lengthy production process may lead to a conclusion that the patentee has suffered little deprivation. The number of instances of use made of the patented product or process. Where the same patented product is used repetitively through the production of the non-patented end product, there may be clearer evidence that the advantage of the patentee has been impaired. The strength of the evidence demonstrating that, if carried out or used in Canada, the product or process would constitute infringement. On this point, my opinion would be that, where there is ambiguity in the evidence, the benefit of the doubt should go to the party using the product or process. This is, perhaps, simply another way of expressing the established principle that the patentee bears the burden of proving infringement. The court concludes that a "strong link" must be "established between the use of the patented process or product and the product sold into Canada." Inducement or contributory infringement It is a patent infringement to induce someone else to infringe a patent. A patent can be a composition of unpatented components; the patent would cover the inventive step of selecting and assembling those components. Manufacture of the unpatented components would not be an infringement of the patent unless the manufacturer induces the recipient of those components to infringe the patent. Windsurfing International Inc. v. Trilantic Corp. dealt with a manufacturer selling the unassembled components of a patented sailboard. In the court's decision, Urie J stated: Without assembly there can be no purpose in a purchaser buying the unassembled parts since, unassembled, they cannot be used for the purpose for which they are purchased, that is, to sail. To suggest that a patent infringement suit can be successfully avoided by selling parts as components of a kit in contradistinction to their sale assembled is, in my view, errant nonsense. In MacLennan v. Produits Gilbert Inc., the court established a three-pronged test to determine whether there has been an inducement: There must be an act of infringement by the direct infringer. This act must