[2] In a case where a lessee continuously occupied a leased building after the termination of the lease but fails to use or benefit from the leased building according to its original purpose, whether the obligation to return unjust enrichment is established (negative)

[2] In a case where the lessee continued possession of the leased building part to refuse the return of the object by exercising the right of defense for simultaneous performance even after the termination of the lease contract, but where the lessee was unable to use or benefit from it according to the original purpose of the lease contract, and there was no substantial benefit, it does not lead to the lessee’s obligation to return unjust enrichment even if the lessor

In general, if a claim with a offset exists between the parties, it shall be in principle set-off. The claim subject to such offset shall not be limited to a claim directly accrued between the other party, but shall include a claim acquired from a third party on the ground of transfer, etc. It is based on the fact that the status of the person entitled to set-off is legally protected by law by settling the claim with a simple method of payment of the claim and the debt, the original purpose of which is to facilitate and equitable the obligation of both parties by settling the payment of the set-off system in conflict with each other, and that for a person who intends to exercise the right of set-off, the existence of the claim is practically a function as a security for the automatic claim, and thus, the reasonable expectation of the parties to the function as a security

Therefore, in light of the purpose and background of acquiring the claim or obligation subject to a set-off and the specific and individual circumstances leading to the exercise of the right of set-off, if it deviates from the purpose and function of the set-off system as above and there is no value to be legally protected, the exercise of the right of set-off is reasonable to be prohibited as it abuse of the right to set-off against the good faith principle or its right to set-off, and in light of the foregoing grounds that restrict the exercise of the right of set-off, it does not require any subjective requirement required for abuse

According to the facts established by the court below, the Plaintiff, while being aware of the fact that the value of the promissory note issued by the Daejeon department store was significantly diminished due to the bankruptcy of the Daejeon department store, was set off and acquired at a price below 40% of the face value, and the amount of the promissory note at a price below 40% of the face value, was set off against the lease deposit repayment obligation to be borne by the Daejeon department store.

Therefore, in light of the purpose and background of acquiring the above promissory note claim, the amount paid as compensation, and the above circumstances, the right to offset, the Plaintiff’s exercise of the right to offset deviates from the purpose and function of the set-off system, and it is not permitted as it constitutes a case where there is no legitimate expectation for the legal conflict of claims and the function of securing the obligation, and it is contrary to the good faith principle or an abuse of the right

The court below's rejection of the plaintiff's allegation in the same purport is just, and there is no error in the misapprehension of legal principles as to mistake of facts or set-off, assignment of claims, and abuse of rights.

2. As to the Defendant’s ground of appeal

A. The judgment of the court below

In full view of the evidence of employment, the lower court determined on April 23, 1993 that the Plaintiff leased deposit 202,886,000 won, monthly rent 2,233,800 won, and rent 2,300 on June 30, 1997 between the Daejeon department store and the Plaintiff on April 23, 1993 (hereinafter “instant store”) from among the real estate listed in the attached list as indicated in the judgment of the lower court, which was owned by the Plaintiff, to the extent of June 30, 1997. The above lease contract was explicitly renewed, and Daejeon department store transferred its claim for the return of the above lease deposit to the Defendant on March 20, 200, with the notice of termination of the lease contract and the notice of assignment of claim to the Plaintiff on March 20, 200, Daejeon department store did not pay rent to the Plaintiff on or after October 8, 199, which was unilaterally recognized as the obligation to return the lease deposit to the Plaintiff without any special circumstances.

B. The judgment of this Court

Although a lessee continued possession of the leased building part to refuse the return of the object by exercising the right of defense for simultaneous performance even after the termination of the lease agreement, in case where the lessee did not gain any profit by failing to use or benefit from the leased building according to the original purpose of the lease agreement, even if the lessor suffered any loss due to such failure, the lessee’s obligation to return unjust enrichment shall not be established (see, e.g., Supreme Court Decisions 98Da8554, Jul. 10, 1998; 2000Da61398, Feb. 9, 2001).

However, according to the records, the location of the leased object under the lease agreement concluded on April 23, 193 by the Plaintiff and Daejeon department store was indicated in Dong-gu, Daejeon (location omitted). The size of the leased object was 14.1 (Records No. 24) and the preparatory documents submitted by the Plaintiff himself are leased 14.5 (Records No. 259). On the other hand, as indicated in the attached list in the judgment of the court below, the Plaintiff owned a total of 215.1 square meters from the first to the fifth, office building and underground office as stated in the judgment of the court below. The former lease agreement concluded on April 23, 1987 between the Plaintiff and Daejeon department store that did not use the leased object as an indirect leased object, and the court below should have determined that the leased area of the leased object was less than 1 to 5th, 216.9 square meters from the date of lease agreement concluded on August 23, 2002.

Nevertheless, the court below's decision that the amount of monthly rent should be deducted until the date of the order of the store of this case solely based on its stated reasoning is erroneous in the misapprehension of facts or in the misapprehension of legal principles as to unjust enrichment, which affected the conclusion of the judgment. The ground of appeal pointing this out is with merit.

3. Conclusion

Therefore, the part of the lower judgment against the Defendant is reversed, and that part of the case is remanded to the lower court for further proceedings consistent with this Opinion. The Plaintiff’s appeal is dismissed. It is so decided as per Disposition by the assent of all participating Justices on the bench.

Justices Son Ji-yol (Presiding Justice)