This common ownership is distinct from a common-property resource. In the latter case, common property is misused because no one has the right to exclude. But here, the common ownership means that a single decision maker takes actions that reflect the costs and benefits to the parties with which he or she deals. Transactions costs are not eliminated, but they are greatly reduced in comparison to a situation in which the shopowners negotiated directly with each other over payments for customers drawn to their adjacent locations. It is not hard to uncover other examples of market devices designed to internalize potential externalities concerning customers drawn to retailers.
Manufacturers sometimes demand that their retailers handle their products exclusively.
Other examples of single ownership to internalize externalities. Unitization Virtually all domestic reservoirs involve multiple ownership, often by persons with different aims and objectives. And yet, it is absolutely basic that a reservoir shold be handled as a unit operation in order to achieve maximum oil recovery from it. Oil and gas fields present important potential externality problems. The rights to drill into a reservoir of oil are owned by the surface landowners.