“…Comparing licensing by means of upfront fees (which may be collected via an auction) and royalties, the early literature concluded that licensing by means of upfront fees dominates royalty licensing for an outside innovator (Kamien & Tauman, 1984;Kamien & Tauman, 1986;Kamien, et al, 1992). As royalties are frequently observed in practice, the conclusion on the suboptimality of royalty licensing generated a number of papers that argued that royalties can be explained by factors, such as informational asymmetry (Gallini & Wright, 1990;Rockett, 1990;Sen, 2005a), product differentiation (Muto, 1993;Wang & Yang, 1999;Poddar & Sinha, 2004), leadership structure (Kabiraj, 2004;Kabiraj, 2005;Filippini, 2005), or by the fact that the number of licenses must be an integer (Sen, 2005b). There is a small literature that considers issues of international trade in the context of technology transfer.…”