Marco Ottaviani (Department of Economics) published Competition through Commissions and Kickbacks in American Economic Review, Volume 102, No. 2, April 2012, pag. 780-809, doi: 10.1257/aer.102.2.780, with Roman Inderst (Goethe Universität Frankfurt).
Abstract: In markets for retail financial products and health services, consumers often rely on the advice of intermediaries to decide which specialized offering best fits their needs. Product providers, in turn, compete to influence the intermediaries' advice through hidden kickbacks or disclosed commissions. Motivated by the controversial role of these widespread practices, we formulate a model to analyze competition through commissions from a positive and normative standpoint. The model highlights the role of commissions in making the advisor responsive to supply-side incentives. We characterize situations when commonly adopted policies such as mandatory disclosure and caps on commissions have unintended welfare consequences.