Debate over the merits of patents versus inducement prizes has tended to ignore the signaling roles of patents, and totally ignores the impact of patent signaling on prize contests. This paper asks: How does patent signaling affect the strategic choices of firms considering entering prize contests? First, we consider contests that do not allow patenting, then contests that do. If patenting is not allowed, we argue, patent-holders, both internal and external to the contest, can adversely impact prize contests by claiming prize winner violation of their patents, and suing for damages. The likelihood of such challenges being made can deter entry, particularly in contests requiring large sunk costs. Furthermore, the firm's decisionmaking process will discriminate against entering prize contests and favor R&D projects with patentable outcomes. Together, these problems may circumscribe any future wider role for prize contests, and limit their major putative welfare advantage: the ability to place prize winning solutions into the public domain. In contests where entrants may patent their inventions, entry is subject to basically the same problems as above (although such contests may carry some advantages as regards contest design). Our overall conclusion is that prize contests are liable to fail due to the lack of potential entrants, particularly as regards entry on the part of larger commercial firms
