Independent Invention Defense in Intellectual Property
The authors of the report argue that the patent rule is inferior in any industry where the cost of independently inventing a product is not too much less than the inventors cost. They contend that the threat of independent invention creates a mechanism that limits patent holders profits to levels commensurate with their costs of research and development.
Link
http://www.dklevine.com/archive/scotchmer-independent-invention.pdf