15.21 Derivative Liability-Contributory Infringement is the legal principle that holds someone liable for the infringement of another’s intellectual property rights even if they did not personally commit the infringement. This liability is based on the principle that a person or entity has contributed to the infringement through either providing the goods or services that enabled the infringement or actively inducing or encouraging someone else to do so. This type of liability can be found in the Copyright Act, Patent Act, and Trade-Marks Act of Canada. There are two main types of derivative liability-contributory infringement: direct infringement and indirect infringement. Direct infringement occurs when someone or an entity provides the goods or services that enable another to infringe upon another’s intellectual property rights, while indirect infringement occurs when a person or entity actively induces or encourages someone else to commit the infringement.