 However, at least in principle the owner of the first shopping centre can avoid this by purchasing the surrounding land before free parking is allowed. After Ronald Coase this mechanism for solving externalities problems is referred to as “extending the role of the firm” (see Demsetz 1964). Another example for this mechanism involves the public good pollination. If a bee keeper and the owner of an orchard cannot agree on the value of the pollination and nectar, either is free to buy the other’s property and thus internalise the externality by extending the firm.