A coase solution to a problem of externality ensures that a socially efficient outcome is to

A coase solution to a problem of externality ensures that a socially efficient outcome is to maximize the joint welfare, irrespective of the right of ownership.

Explanation:

In law and in economics the Coase theorem explains the economic efficiencies in the existence of externalities. The economic efficiency of economic allocation or outcome. In practice, barriers to negotiation or poorly defined rights of property can prevent coasean negotiations.

The private external solutions include, for the benefit of the relevant parties, moral codes, charities and business fusions and contracts. In the theorem, two parties can bargain and obtain an optimal outcome in the presence of an externality when transaction cost is low.