Of the principal lawsuit of the lower judgment, the part against the Plaintiff (Counterclaim Defendant) regarding the conjunctive claim for return of unjust enrichment.

The grounds of appeal are examined.

1. The principle of free evaluation of evidence declared by Article 202 of the Civil Procedure Act means that it does not need to be bound by the formal and legal rules of evidence, and does not allow a judge’s arbitrary judgment. The recognition of facts shall be in accordance with logical and empirical rules based on the probative evidence duly admitted as evidence, and even if the fact-finding belongs to the discretion of the fact-finding court, it shall not exceed the limit (see, e.g., Supreme Court Decision 2009Da7198,7204, Apr. 13, 2012). In addition, if it is obvious that the parties fail to prove or are at issue due to care or misunderstanding, or there is no explicit dispute between the parties as to the matter, the court shall request the submission of testimony and certification, and if the court intends to determine the propriety of the claim on the ground that the parties did not have been aware of at least or have not anticipated, it shall give the parties an opportunity to state their opinions, and it shall not be deemed that the Plaintiff did not exercise the duty of return the Plaintiff’s 2000.