1. The judgment of the court of first instance is modified as follows.

The defendant shall pay to the plaintiff KRW 39,613,450 as well as to the plaintiff on December 2016.

1. As to claim for the purchase price

A. According to the evidence Nos. 2-1, 2, and 9 of the judgment on the cause of the claim, the Plaintiff sold two parts of construction machinery (Ccheon air and Dcheon air) to the Defendant around September 2014 at KRW 110,00,000 (hereinafter “the instant purchase price”) and completed the procedures for ownership transfer registration in each of the Defendant’s future on October 6, 2014 with respect to Dcheon air.

In addition, the Plaintiff paid KRW 50,00,000 out of the instant purchase price to the Plaintiff on October 22, 2014, and the Plaintiff’s creditor G was issued a collection order as to KRW 15,139,360 among the Plaintiff’s claim for the instant purchase price as Seoul Southern District Court Decision 2017TTT953 on July 20, 2017, as to KRW 15,139,360 among the Plaintiff’s claim for the instant purchase price. The Plaintiff’s creditor is the Daejeon District Court Branch Branch 2017TTT309 on February 13, 2017.

According to the above facts, the defendant is obligated to pay to the plaintiff 39,613,450 won (=10,000,000 won - 15,139,360 won - 5,247,190 won - 15,139,360 won - 5,247,190 won) and damages for delay after deducting the claim amount of each of the above claims attachment and collection order from the total amount of KRW 50,000 and the remainder of the sales amount of KRW 39,613,450.

B. The Defendant’s defense of offsetting the amount of KRW 17,00,000 in operating income is asserted as follows: (a) around the end of 2015, the Defendant agreed to divide half of the subcontracted construction income from E Co., Ltd. (hereinafter “E”) to the Defendant instead of continuously working for the Plaintiff’s company; and (b) thus, the Defendant should offset the amount of KRW 17,00

On the other hand, the existence and scope of the automatic claim in claiming a set-off is liable to assert and prove it to the claimant (see Supreme Court Decision 2016Da255422, Feb. 9, 2017).