Supervisor: dots. Martin Käerdi
Opponents: prof. Christian von Bar (Universität Osnabrück) ja dr iur Triin Uusen-Nacke (Tartu Maakohtu kohtunik)
Unjustified enrichment law is most often applied in order to reverse failed transactions but it also covers other kinds of cases where someone has obtained a benefit at the expense of another without there being a legal ground for that. One of such cases can be described as making expenditures on another person's property without any legal ground therefor. In some European jurisdictions a separate type of unjustified enrichment claim has been developed to solve cases regarding such expenditures. This claim is called condiction of expenditures (or expenditure condiction). The central issue of this dissertation is the question of whether the regulation of expenditure condiction in Estonian law enables to achieve a balance between parties' interests in a situation where a person has incurred expenditure with regard to another person's property without a basis arising from law or an agreement between the parties. In order to answer that question, the author has analysed the historical development of expenditure condiction, it's nature and functions and how to distinguish this condiction from other non-contractual claims which provide for compensation for expenditure incurred with regard to another person's property. The author has concluded that a balance between parties' interests can be achieved if in determining the prerequisites, the content and the extent of expenditure condition it is taken into account that the function of that condiction is restitution of the deficit in creditor's assets. This means that the debtor's enrichment cannot be regarded as a prerequisite of the claim but as a criterion for determining the extent of the claim, and that the extent of creditor's claim can not exceed the value of expenditure. In addition, when construing the prerequisites of the expenditure condiction, its interrelations with other institutes of civil law on one hand, and its nature as a restriction of the general enrichment action on the other hand must be taken into account. Also, the author has concluded that in determining the extent of the claim under expenditure condiction, it is necessary to apply an approach which enables to modify the debtor's liability pursuant to his good or bad faith.