유류분반환청구권의 법적 성질 - 불소급형성권설을 중심으로

The Legal Nature of the Claim for the Return of the Forced Portion : Focusing on the ‘non-retroactive formative right theory’

The legal nature of the claim for the return of the forced portion has been in conflict between the formative right theory and the claim right theory. The formative right theory holds that if a forced portion right holder exercises the claim for the return of the forced portion, any donation or legacy that infringes upon the forced portion will be retroactively rendered ineffective. Case law supports the formative right theory. On the other hand, the claim right theory holds that if a donation or legacy that infringes upon the forced portion has already been performed, the forced portion right holder has a right of claim that allows him or her to demand the return from the donee or legatee, and if it has not yet been performed, he or she has a right of defense that allows him or her to refuse performance, but the effect of the donation or legacy will not be lost. The formative right theory has the advantage of clarifying the legal relationship regarding the return of the forced portion, but has the disadvantage of undermining the safety of transactions. On the other hand, the claim right theory has the advantage of promoting the safety of transactions, but has the disadvantage of making the legal relationship regarding the return of the forced portion unclear. Accordingly, I believe that the ‘non-retroactive formative right theory’ is valid. The non-retroactive formative right theory is the view that a donation or legacy that infringes on the forced portion loses its effect from the time of the claim for the return of the reserved portion. According to the non-retroactive formative right theory, the legal relationship regarding the return of the forced portion becomes clear, and the safety of transactions can be ensured, eliminating the disadvantages that arise when adopting the formative right theory and the claim right theory. The legal relationship regarding the return of the forced portion according to the ‘non-retroactive formative right theory’ is analyzed as follows: ① If a donation or legacy that infringes on the forced portion is performed, the method of returning the forced portion is based on the legal doctrine of return of unjust enrichment. In other words, the person with the forced portion right can, in principle, request the return of the original object, and if the return of the original object is impossible, the return of the value can be requested (the Korean Civil Act Article 747). ② The fruits acquired by the donee or legatee from the object subject to the return of the forced portion before the request for return of the reserved portion may be retained by the donee or legatee, and the fruits acquired after the request for return must be returned according to the legal doctrine of return of unjust enrichment (Article 748). ③ If the donee or legatee transfers the object of the donation or legacy to a third party, the person with the forced portion right cannot request return from the assignee, and can only request return of the value from the donee or legatee (Article 747). The assignee may retain the acquired rights.