(a) Where a sub-contractor contract is null and void because it violates the Mining Industry Act, the joint mining right registration with limited liability and the legal relationship on the payment of deposit;

(b) Whether Article 536 of the Civil Act which provides a right of defense of simultaneous performance applies mutatis mutandis where a bilateral contract becomes null and void and void and each party's obligation to reinstate is fulfilled.

A. Even if a subcontractor’s contract is null and void due to its violation of the Mining Industry Act, since the joint mining registration or the payment of deposit is not a violation of the public order and commitment, it cannot be deemed an illegal cause. Thus, the court may order the procedure for registration of withdrawal from the joint mining right holder’s name to the procedure for registration of withdrawal from the joint mining right holder’s

B. The purport of Article 536 of the Civil Act, which prescribes the right to reply to simultaneous performance, is due to the merger between the concept of fairness and the principle of good faith, and Article 549 of the same Act applies mutatis mutandis to the termination of a contract pursuant to Article 549 of the same Act, even in cases where a bilateral contract becomes null and void, and each party should return each other's acquisition thereof, it is right to apply mutatis mutandis the Civil Act Article 536 of the same

[Judgment of the court below]

Defendant

Seoul High Court Decision 74Na1992 delivered on May 29, 1975

The judgment below is reversed and the case is remanded to Seoul High Court.

The grounds of appeal are examined.

1. The records are examined. The judgment of the court below which rejected the defendant's assertion that the registration of joint mining rights under the name of the original defendant, which was at issue in this case, was made in connection with the so-called So-called So-called So-called So-called So-called So-called So-called So-called sublet contract to guarantee the defendant's status as a sub-contractor, and was made by donation separately, is acceptable, and there is no violation of the rules of evidence or misapprehension of the legal principles, such as the theory of lawsuit, and the above sub-contractor contract is in violation of Article 13 of the Mining Industry Act, and thus, the judgment of the court below that

2. According to the decision of the court below, the defendant paid 2,500,000 won to the plaintiff and the plaintiff registered the transfer of mining right under the joint name with the defendant for the purpose of guaranteeing the sub-contractor contract of this case. Thus, even if the sub-contractor contract of this case violates the above Mining Industry Act and becomes null and void, the joint mining right registration of this case or the payment of deposit is not in violation of the public order and good faith, and it cannot be deemed an illegal cause of payment (see Supreme Court Decision 63Da466 delivered on October 31, 1963). Thus, the decision of the court below ordering the procedure for the cancellation of joint mining right under this premise is justifiable, and this shall be the same as the return of deposit.

However, the court below rejected the defendant's defense of simultaneous performance on the ground that the above joint mining right registration and the payment of deposit between the plaintiff and the defendant were made in order to guarantee the above sub-contractor contract, which is made legally null and void, and the joint mining right withdrawal is not governed by the general provisions of the contract on the rescission of contract. Thus, the defendant's joint mining right withdrawal registration obligation and the plaintiff's above joint mining right withdrawal registration obligation under the joint mining right withdrawal registration procedure cannot be viewed as a payment which has the nature to be fulfilled as repayment which has the legal meaning of the deposit return obligation under the law. However, in relation with the bilateral contract under Article 536 of the Civil Act, the purport of Article 536 of the Civil Act that each party may refuse the performance of his own obligation until the other party's obligation is provided for the other party's obligation under the bilateral contract is in accord with the concept of fairness and the principle of good faith and that Article 549 of the Civil Act applies mutatis mutandis to the restoration of obligation of each party arising from the rescission of contract.

If a contract is null and void under the concept of fairness, there is no reason to distinguish it from the obligation of restitution when the contract is null and void, and there is no reason to distinguish it from it at the time of the termination of the contract, and only one of the parties is forced to perform the obligation first, it is contrary to the principle of fairness and good faith.

Therefore, since the defendant's right to claim the above deposit and the joint mining right of this case were created in the same legal relationship, which is invalid in the procedure for the joint registration and withdrawal of the above joint mining right, the above joint mining right of this case has a relation with each other, and it is also a simultaneous performance relationship. Therefore, the above original judgment of this case has an error of law by misunderstanding the legal principles of simultaneous performance.

Therefore, the judgment of the court below is reversed and it is so decided as per Disposition by the assent of all participating judges.

Justices Yang Byung-ho (Presiding Justice)