We develop a theoretical framework of trade on a platform on which buyers and sellers interact, and compare the impact of different platform ownership structures. If two-sided network effects are strong, monopoly ownership induces more trade than dispersed ownership and is therefore socially...

Alliances between competitors in which established firms provide access to proprietary resources-for example, their distribution channels-are important business practices. We analyze a market where an established firm, firm A, produces a product of well-known quality, and a firm with an unknown...