Abstract
Patents and copyrights are special forms of immaterial property that grant to their owners the exclusive right to control the production and sale of a specified producta literary or artistic work in the case of copyrights, an invention or productive process in the case of patents. Often these concepts are subsumed under a broader concept of intellectual property, but they are not completely analogous and cannot always be justified with the same arguments. The term intellectual property also covers some other very different concepts, such as trademarks. Unfortunately, in recent discussions of these topics the concept of intellectual property is often used generically, blurring some important practical distinctions.