1. The judgment of the court below

According to the reasoning of the judgment below, the court below, based on the evidence of employment, concluded a sales contract to sell the commercial building of this case to 23 billion won with a co-defendant Ga Co-Defendant Ga Co-Defendant Ga Co-Defendant Ga Co-Defendant Ga (hereinafter referred to as "Gail Distribution"), and confirmed the sales business by dividing the commercial building of this case from that time to that time. The plaintiffs concluded a sales contract to each part of the contract object column among the contract and payment details attached to the court below among the commercial building of this case, and concluded a sales contract to sell the commercial building of this case with a unit by unit. The court below determined that the defendant did not have the right to receive part of the sale price as stated in the above contract and payment details among the commercial building of this case, and the defendant did not have the right to receive part of the sale price from the defendant to 23 billion won, and the defendant did not have the right to receive part of the sale price from the plaintiff to 39 billion won, and it did not have the right to receive part of the sale price from the commercial building of this case.

2. Judgment of the Supreme Court

The above judgment of the court below is hard to accept for the following reasons.

If a party to a contract directly provides a third party who has a different contractual relationship with the other party by shortening the performance process through the instruction of the other party to the contract, etc., the party to the contract may not file a claim for return of unjust enrichment on the ground that he/she received the payment against the third party without any legal cause.

However, according to the facts acknowledged by the court below, although the actual payment relationship in this case occurred between the plaintiffs and the defendant, it can be seen that the payment for the provisional distribution of the plaintiffs and the payment for the defendant for the provisional distribution was made in accordance with the above legal principles. Thus, the defendant's receipt of the sale price from the plaintiffs is justified as it is based on a contractual relationship with the provisional distribution, and therefore, the plaintiffs cannot make a claim for return of unjust enrichment to the defendant.

In addition, the court below determined that the plaintiffs can exercise their right to claim restitution of unjust enrichment even after the contract was lawfully rescinded between the virtual distribution. However, in light of the record, the plaintiffs did not assert that the above contract was rescinded, and even if the plaintiffs lawfully rescinded the above contract, the liquidation of the contract should be conducted between the virtual distribution and the party who is the other party to the contract, and the payment of the purchase price against the defendant can not be claimed for return on the ground that it is unjust enrichment. If the plaintiffs can claim the return of unjust enrichment directly against the defendant who is a third party, it would result in the violation of the basic principles of contract law by transferring the risk burden to the third party under their own responsibility, and it would be improper for the third party who is the beneficiary to violate the right of defense against the other party to the contract.

Nevertheless, the court below erred by misapprehending the legal principles as to unjust enrichment and thereby adversely affecting the conclusion of the judgment. The defendant's ground of appeal assigning this error is with merit.

3. Conclusion

Therefore, the part of the judgment below against the defendant is reversed, and that part of the case is remanded to the court below for a new trial and determination. It is so decided as per Disposition by the assent of all participating Justices.

Justices Zwon-won (Presiding Justice)