A person who has taken out a marine insurance policy may also have a claim against a third party if loss has been caused by him. In such a case the assured will have two remedies, one from the insurer and one from the third party. Subrogation places the insurer in the position of the assured with regard to the third party. The double recovery is then prevented and the third party is not relieved from his wrongdoing by the insurer's payment. Allocation of recovery from the third party is rather complex and it should be to determine whether the policy is valued or unvalued and then whether the loss is total or partial in nature. Subrogation may be excluded or modified by the terms of the policy such as joint and composite policies. Subrogation and abandonment are distinguished in several respects. The doctrine of abandonment is itself based upon the principle of indemnity.