1. Of the part of the first instance judgment’s claim for restitution of unjust enrichment, the payment order exceeds the following amount.

1. Determination on the legitimacy of a counterclaim

A. The Plaintiff’s main defense of this case’s counterclaim is unlawful, since the Defendant’s counterclaim was filed by the appellate court, and it cannot be consented to the Plaintiff’s allegation of counterclaim by impairing the Plaintiff’s interests.

B. Counterclaim in the appellate court’s judgment may be instituted in cases where there is no possibility of undermining the interests of the other party’s instance pursuant to Article 412(1) of the Civil Procedure Act, or where consent of the other party is obtained

Here, “cases where there is no possibility of undermining the other party’s interest in the other party’s instance” refers to cases where a substantial issue constituting the basis of a counterclaim is sufficiently examined in the first instance court in relation to the cause of the principal claim or method of defense, and there is no concern that the other party may lose the other party’s interest

[See Supreme Court Decision 201Da77351, Dec. 8, 2011 [see, e.g., Supreme Court Decision 2011Da77351, 77368] In light of the aforementioned legal principles, the Defendant filed a counterclaim on Nov. 8, 2019, stating that “The Defendant loaned the Plaintiff KRW 3 million on April 20, 201, KRW 200,000,000 on April 27, 201, KRW 4 million on June 14, 2011, and KRW 9 million on a total, to the Plaintiff” (see, e.g., Supreme Court Decision 201Da77368, Nov. 8, 2019).

However, considering the fact that the parties have never asserted or examined the above loans in the first instance court, it is likely that the court’s hearing of the counterclaim in this case would prejudice the interests of the plaintiff in the court of first instance.

In addition, since the Plaintiff expressed his/her intent to consent to the counterclaim of the Defendant through a preparatory document dated November 13, 2019, the counterclaim of this case by the Defendant is unlawful against Article 412(1) of the Civil Procedure Act.

2. Judgment on the plaintiff's main claim

A. The reasoning of the judgment on this part of the facts of recognition is from 10 to 3.2 of the judgment of the first instance.