What is contributory infringement?

Contributory infringement is one of the two types of indirect copyright infringement (vicarious infringement is the other type of indirect infringement). Contributory infringement occurs where someone knows that infringing activity is taking place and either induces it, causes it, or materially contributes to it. So there are two elements required to proving contributory infringement - that the infringer knew or had reason to know of the infringing activity (which differs from direct infringement, where the infringer doesn’t have to have any knowledge or intent) and active participation in the infringement (which can include inducing it, causing it or contributing to it). So for example, if your brother has made infringing copies of a CD, and you know these copies are infringing and help create an e-bay listing for your brother to sell the discs, you have committed contributory infringement.