Since Civil Law recognizes the freedom of a testament, it recognizes the freedom allowing the decedent to dispose his/her own property at his/her own intention. However, in order to prevent various abuses which may occur when the principle of freedom of testament is carried out unlimited, secured portion system is stipulated. So, absolute freedom of property disposed by the deceased is limited. Likewise, the secured portion system is introduced as the system to resolve the contradiction that exists between principle of freedom of testament and legal inheritance. Since Supreme Court Decision 2010DA50809 delivered on May 24, 2012 includes major legal issues such as how to exercise of claim of return for secured portions, transfer of the secured proportion or the claim of return for secured portions, and exercise of claim of return for secured portions against a third party. So, it has a very important meaning. In this paper, legal issues regarding the exercise of claim of return for secured portions have been reviewed with this decision.