1. The court below affirmed that the real estate in this case was KRW 3,158,600 at the market price as of August 8, 1974, and held that the Plaintiff’s act of selling the real estate to Defendant 1 for about 8 minutes at the market price was unfair, or that the Plaintiff’s act of selling it to Defendant 1 for about 380,000 won, which is about 8 minutes at the market price, was unfair. However, in order to constitute a null and void juristic act as it falls under Article 104 of the Civil Act, the court below rejected the Plaintiff’s assertion that there was a significant difference in the purchase price, and that the other party was in a rash, experience, and poor condition, and that the other party entered into such contract with the knowledge of such circumstances. The court below rejected the Plaintiff’s assertion that the testimony by Nonparty 1 and Nonparty 24 of the first instance trial and Nonparty 2 of the court below did not have any evidence to acknowledge it solely, and there was no other evidence to nullify Article 104 of the Plaintiff’s Civil Act.

2. In order to assert the invalidity of a juristic act by Article 104 of the Civil Act, the plaintiff's assertion that the juristic act has been done with old time, rashness or experience on the part of the plaintiff's assertion, and the other party should assert and prove that the juristic act has been done by using it, and it is presumed that the juristic act has considerably lost its fairness, and it would have been done with old time, rashness or experience, and it is not presumed that it would have been done with old time, rashness or experience, but it is reasonable in the party's precedent or party members (see Supreme Court Decision 75Da704 delivered on April 13, 1976). It is sufficiently agreed with the records of this case's purchase and sale price as recognized by the court below at the time of 00 10 minutes, and it is hard to see that the plaintiff's purchase and sale price of the real estate at 10,000 won and 40 times it is hard to see that the plaintiff's new evidence and 14.

If so, the court below did not err in finding facts falling under Article 104 of the Civil Act as alleged by the plaintiff because it violated the Inheritance and Gift Tax Act, and since the illegality did not have affected the conclusion of the judgment in this case, it should be viewed that the argument pointing this out is well-grounded.

Therefore, the original judgment is reversed in accordance with the provisions of Articles 400 and 406 (1) of the Civil Procedure Act, and the case is remanded to the Seoul High Court which is the original judgment. It is so decided as per Disposition by the assent of all participating judges.

Justices Min Jae-chul (Presiding Justice)