1. The plaintiff's appeal is dismissed.

2. The costs of appeal shall be borne by the Plaintiff.

The purport of the claim and appeal is the purport of the appeal.

1. The reasoning for this part of the underlying facts is as stated in the reasoning of the judgment of the court of first instance, except for the addition of “B No. 3” to the grounds for recognition. Thus, this part of the reasoning is cited by the main sentence of Article 420 of the Civil Procedure Act.

2. The assertion and judgment

A. The Plaintiff’s assertion 1) The Defendant, the purchaser of each of the instant real estate, or E, the Defendant, or the Defendant’s agent, had concluded the instant sales contract by deceiving the seller’s net C as follows. As such, the Plaintiff revoked the instant sales contract on the grounds of deception by the Defendant, etc. (A) and the market price of each of the instant real estate was KRW 60 million at the time of the instant sales contract. The Defendant and E were aware that the market price was much much less than the actual market price.

B) The Defendant and E did not properly notify the buyer of the fact that he is the E’s father. (2) The net C concluded the instant sales contract with the omission of error in the market price of each real estate of this case. However, since the sales price agreed in the instant sales contract falls short of the officially announced value, the sales contract of this case is revoked on the grounds of mistake, and thus, the sales contract of this case is revoked on the grounds of mistake. (b) Even if the mistake in the purchase price was caused by mistake in the motive, it constitutes an error caused by the Defendant or the Defendant’s agent E and constitutes an error in the important part. Therefore, the instant sales contract is revoked on the grounds of

3) At the time of the instant sales contract, the deceased C was at the age of 97 years, and the important property decision was at the discretion of E. Therefore, it should be deemed that E entered into the instant sales contract on behalf of the deceased C.

B. At the time of the instant sales contract, E, as seen above, entered into the instant contract on behalf of the Defendant who is the buyer at the same time, or entered into the sales contract on behalf of the buyer.