1. All appeals filed by the plaintiffs and the claims added by this court are dismissed.

2. After an appeal is filed.

1. The reasoning for this part of this Court’s reasoning is as stated in Paragraph 1 of the reasoning of the judgment of the court of first instance, and thus, this part is cited in accordance with the main sentence of Article 420 of the

2. The plaintiffs' assertion

A. Although the instant subcontract expressly states that there was no material to be paid by the subcontractor to the subcontractor (Defendant) in the instant subcontract, the Cheongfriendly Development bears the material cost equivalent to KRW 580,161,71 in total between October 201 and December 2012 in relation to the instant framework construction.

In addition, F received a sub-subcontract from the Defendant, and as the Defendant did not pay the construction cost, F received a final and conclusive judgment in favor of the Plaintiff A by filing a civil suit seeking payment of KRW 33,035,000 for the construction cost.

(In the final and conclusive judgment, the amount ordered the Plaintiff A to pay the final and conclusive judgment (hereinafter “judgment money”). Accordingly, the Plaintiff placed the place where the payment of the judgment money is to be made to F on behalf of the Defendant.

B. As above, the Defendant agreed to pay the materials cost and judgment amount paid or to be paid by the public good development to the public good development.

(B) However, the Defendant is obligated to compensate for the damages incurred as a result of the Defendant’s failure to perform his/her obligation under the instant subcontract, resulting in damage equivalent to the said material cost and judgment amount, and as such, without any legal cause, the said material cost and judgment amount was profit-making and the damage equivalent to the said amount was incurred in the Cheong-do Development. Therefore, the Defendant is obligated to return the said amount as unjust enrichment.

(Preliminary Claim). (c)

on November 29, 2016, the Cheongri Development transferred to the Plaintiff A a claim for the above agreement, compensation for damages, or return of unjust enrichment with respect to the Defendant. On November 30, 2016, the Defendant notified the assignment of the above claim to the Defendant. On January 31, 2017, the Plaintiff A transferred KRW 400,000 out of the above claim against the Defendant to the Plaintiff B, and the Plaintiff transferred KRW 400,000 among the above claim against the Defendant.