The Economics of Product-Line Restrictions with an Application to the Network Neutrality Debate

Abstract

We examine the welfare effects of product-line restrictions, such as those called for by some proponents of network neutrality regulation. We consider a platform that brings together households and application providers. We find that restricting a monopoly platform to a single product has the following effects: (a) application providers that would otherwise have purchased a low-quality variant are excluded from the market; (b) applications in the middle of the market utilize a higher and more efficient quality; and (c) applications at the top utilize a lower and less efficient quality than otherwise. Total surplus may rise or fall, although the analysis suggests to us that harm to welfare is likely. We also examine a duopoly model and find that the welfare effects are similar.