Free Entry under Common Ownership

This study investigates the equilibrium and welfare properties of free entry under common ownership. We formulate a model in which incumbents under common ownership choose whether to enter a new market. We find that an increase in common ownership reduces entries, which may or may not improve welfare. Welfare has an inverted-U shaped relationship with the degree of common ownership. However, if firms do not have common ownership before the entry, after entry common ownership harms welfare