[2] The case holding that the court below cannot render a judgment ordering future performance on the ground that the ground for non-performance of the obligation to return unjust enrichment equivalent to the rent from the use of and profit from the land in possession exists until the delivery of the land that the court below ordered performance cannot be determined at the time of the closing of argument

[2] The case holding that in case where the defendant's possession of the land in dispute is legitimate because it is subject to the exercise of concurrent performance defense or lien, but the defendant orders unjust enrichment of the amount equivalent to the rent on the ground that the defendant gains a practical benefit by using and making profits from the land according to its original purpose, since the defendant can terminate the use and profit of the land before the "delivery date" that the court below ordered performance although he did not deliver the land to the plaintiff, it constitutes a case where the cause for nonperformance cannot be determined at the time of the closing of argument that the cause for non-performance cannot be determined definitely at the time of the closing of argument.

2. However, it is difficult to accept the fact-finding and determination by the court below in the following respects.

A. First of all, the Defendant’s construction of the instant land is not limited to Nonparty 2’s above restaurant and 2’s size of the instant land, or the Defendant’s construction of the instant land owned and used by Nonparty 1 for up to 1,000 square meters. The Defendant’s construction of the instant land on February 19, 198 with approximately 70 square meters, which was owned by Nonparty 2, including the instant land, was deemed to have occupied all of the instant land with 1 and 3, but the Defendant’s construction of the instant land owned by Nonparty 1 and the instant land owned by Nonparty 2 for up to 1,000 square meters. The Defendant’s construction of the instant land and the instant land owned by Nonparty 2, including the instant 2,000 square meters, on the 2,000 square meters of the instant land, and there is no need for the Defendant to enter the lower court’s construction of each of the instant land on the 2,000 square meters of the instant land.

Nevertheless, the judgment of the court below that recognized that the defendant occupied and used all of the land of this case from August 26, 1989, which was the day following the day when the non-party 1 acquired the ownership of the land of this case 2, to the day is held, is erroneous in the misapprehension of the rules of evidence, thereby affecting the conclusion of the judgment. Thus, the ground of appeal pointing this out is with merit.

B. Next, in order to make a decision ordering future performance, the obligation must continue to exist until the date of the closing of argument, as well as the time the cause for the performance of the obligation arrives in the future. If the period of liability is uncertain and it is impossible to definitely at the time of the closing of argument, a decision ordering future performance shall not be rendered (see, e.g., Supreme Court Decisions 86Meu2151, Sept. 22, 1987; 90Meu25277, Jun. 28, 1991). As seen earlier, each possession of the Defendant’s land and parts of the two land of this case pursuant to the right of simultaneous performance or lien is lawful, and it is not legitimate, but in this case, the Defendant orders unjust enrichment of the amount equivalent to the above land at the time of the closing of argument for the reason that the Defendant gains substantial profits by using and gaining profits from each of the land according to its original purpose, the Defendant may not be determined to continue to use the land in this case until the date of closing of argument.

Nevertheless, the judgment of the court below ordering the defendant to return unjust enrichment until the date of delivery of the land 1 and 2 in this case is erroneous in the misapprehension of legal principles as to the future performance lawsuit. Thus, the ground of appeal pointing this out has merit.

3. Therefore, of the part against the defendant among the part of the judgment below against the plaintiff 1, the part ordering the future performance as of May 19, 200, which is the day following the date of the closing of argument in the court below, and the part against the plaintiff 1's successor to the lawsuit is reversed, and this part of the case is remanded to the court below for a new trial and determination, and the defendant's remaining appeal is dismissed. It is so decided as per Disposition by the assent of all participating Justices.

Justices Song Jin-hun (Presiding Justice)