Of the part of the judgment below's claim for unjust enrichment, 9,376,040 won and damages for delay shall be reversed, and this part shall be reversed.

The grounds of appeal are examined.

1. Even if a lessee allows a third party to use or benefit from the leased object by transferring the right of lease or sub-leaseing the leased object without the consent of the lessor, the lessor still has a right to claim the rent against the lessee unless the lease contract is terminated or the lease contract is lawfully terminated due to other reasons. Therefore, to the extent that the lease remains in existence, the lessor may not claim for damages or claim for restitution of unjust enrichment against the third party on the ground of illegal possession.

(See Supreme Court Decision 2006Da10323, Feb. 28, 2008). However, a lessor who thereafter owns a leased object may file a claim for damages or a claim for return of unjust enrichment against a third party.

2. The Plaintiff asserts that “the Defendant, from November 1, 2012 to January 31, 2013, used each movable property listed in the attached list of the lower judgment, owned by the Plaintiff, thereby gaining profits equivalent to the rent of each of the said movable property without any legal cause and causing damages equivalent to the said rent to the Plaintiff,” and sought a return of unjust enrichment against the Defendant.

In regard to this, the lower court acknowledged the fact that the Plaintiff delivered each of the above movable property to the construction site under the instant lease agreement that the Plaintiff leased temporary materials at the construction site of this case, and that C, who had been performing construction work at the construction site of this case, suspended construction work on September 2012 and the Defendant continued construction and used part of the above movable property while continuing construction, but determined that the Plaintiff cannot file a claim for return of unjust enrichment against the Defendant, who is not the other party to

3. Examining the foregoing legal doctrine in light of the foregoing, the lower court’s determination is difficult to accept.

The judgment below

According to the reasons and records, the Plaintiff, the owner of each of the above movable property, is the lessor.