Patents can be beneficial, but are often harmful

One obvious problem [of patents] is that patents, by definition, create monopolies, which impose costs on the rest of society. For example, the patentee could use its technological monopoly to exploit the consumers… But it is not just the problem of income distribution between the patentee and the consumers. Monopoly also creates net social loss by allowing the producer to maximize its profit by producing at a less than socially desirable quantity… Also, because it is a ‘winner takes all’ system, critics point out, the patent system often results in the duplication of research among competitors – this may be wasteful from the social point of view.

Source: Bad samaritans : the myth of free trade and the secret history of capitalism (Book, 2008) []