Platforms refer to intermediaries that facilitate economic interaction between two sets of agents wherein the decisions of one set of agents is likely to have an effect on the other via direct and/or indirect externalities. Given their nature, platforms need to find the appropriate balance...

We empirically analyze the welfare effects of cross-firm bundling in the pharmaceutical industry. Physicians often treat patients with "cocktail" regimens that combine two or more drugs. Firms cannot price discriminate because each drug is produced by a different firm and a physician creates the...

A large fraction of US public stock is held by institutional investors that frequently hold shares in multiple firms in the same industry ("common ownership"). Concerns have been raised that common ownership might harm competition if it confers influence over important strategic decisions. Using...