Patent systems are often justified by an assumption that innovation
will be spurred by the prospect of patent protection. However, little empirical evidence exists to support this
assumption. One way to test the hypothesis that a patent system promotes
innovation is to simulate the behavior of inventors and competitors
experimentally under conditions approximating patent and non-patent
systems. Employing a multi-user interactive simulation of patent and non-
patent (commons and open source) systems (―PatentSim‖), this studycompares rates of innovation, productivity, and societal utility. PatentSim
uses an abstracted and cumulative model of the invention process, a
database of potential innovations, an interactive interface that allows users
to invent, patent, or open source these innovations, and a network over
which users may interact with one another to license, assign, buy, infringe,
and enforce patents.

Data generated thus far using PatentSim suggest that a system combining patent and open source protection for inventions (that is, similar to modern patent systems) generates significantly lower rates of innovation (p<0.05), productivity (p<0.001), and societal utility (p<0.002) than does a commons system. These data also indicate that there is no statistical difference in innovation, productivity, or societal utility between a pure patent system and a system combining patent and open source protection. The results of this study are inconsistent with the orthodox justification for patent systems. However, they do accord well with evidence from the increasingly important field of user and open innovation. Read the study.