1. The judgment of the first instance court is modified according to the expansion of the purport of the claim in the plaintiff's trial as follows.

The defendant.

1. Basic facts

A. The Plaintiff is a special corporation that is established pursuant to the Marine Environment Management Act and carries out a project for the preservation, management, and improvement of the marine environment.

B. The Plaintiff used “B” vessels with the permission of free use from the Port and Port Authority (hereinafter “instant vessels”), and returned the vessels to the Port and Port Authority as of July 22, 2013.

C. On June 29, 2013, the handoverer prepared by the engineer C at the time of returning the instant vessel to the Plaintiff’s port branch office is indicated as the remainder oil remaining in the instant vessel, which has 780 liters via fuel oil for ship use, and 15,425 liter oil.

After completing the appraisal and assessment of the instant vessel, the Port Port Authority has conducted the open sale procedure, and the Defendant purchased the instant vessel in KRW 233,000,000 in the open sale procedure on October 4, 2013, and concluded a promise to sell and sell the instant vessel to D on October 29, 2013.

E. The Defendant completed the registration of ownership transfer with respect to the instant vessel on November 26, 2013, and completed the registration of ownership transfer again to D and E on the same day. On December 3, 2013, the Defendant paid the remainder of the purchase price of the instant vessel and handed over possession to D, and the Defendant and one other were registered as the owner of the instant vessel on December 4, 2013 in the ship registry.

F. The instant vessel was changed to F on September 3, 2014 by the name of the vessel was changed to F.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1 through 3, Eul evidence Nos. 1 through 4 and 8, the purport of the whole pleadings

2. The parties' assertion

A. When the Plaintiff’s assertion that the ship of this case is sold to the Defendant, the ship fuel oil is not included in the subject of sale, and the Defendant unjust enrichment without any legal ground, and the Plaintiff acquired the claim for return of unjust enrichment from ship fuel to the Defendant of the Port and Port Authority, and thus the Defendant acquired the claim for return of unjust enrichment from ship fuel to the Defendant.