<blockquote>"Given the libertarian understanding of property rights, as sketched above, it is clear that the institutions of patent and copyright are simply indefensible. Patents grant rights in "inventions" — useful machines, or processes. A patent is a grant by the state that permits the patentee to use the state's court system to prohibit others from using their own property in certain ways — from reconfiguring their property according to a certain pattern or design described in the patent, or from using their property (including their own bodies) in a certain sequence of steps described in the patent.
Copyrights pertain to "original works," such as books, articles, movies, and computer programs. A copyright is a grant by the state that permits the copyright holder to prevent others from using their own property — e.g., ink and paper — in certain ways.
In both cases, the state is assigning to A a right to control B's property — A can tell B not to do certain things with B's property. Since ownership is the right to control, IP grants to A co-ownership of B's property. This clearly cannot be justified under libertarian principles. B already owns his property. With respect to him, A is a latecomer. B is the one who appropriated the property, not A. It is too late for A to homestead B's property — B already did that. The resource is no longer unowned.
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However, the argument that the incentive provided by IP law stimulates additional innovation and creativity has not even been proven. It is entirely possible — even likely, in my view — that the IP system, in addition to imposing billions of dollars of cost on society, actually reduces or impedes innovation, adding damage to damage.
But even if we assume that the IP system does stimulate some additional, valuable innovation, no one has established yet that the value of the purported gains is greater than the costs of the system. If you ask an advocate of IP how it is that they know there is a net gain, you get silence in response (this is especially true of patent attorneys). They cannot even point to any study to support their utilitarian contention; they usually point to Article I, Section 8 of the Constitution, as if the back-room dealings of politicians two centuries ago is some sort of evidence."
- Stephan Kinsella,
The Case Against IP: A Concise Guide, 9/4/2009</blockquote>