1. The plaintiff's claims against the defendants are all dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff.

1. Basic facts

A. Defendant B Co., Ltd. (hereinafter “Defendant B”) and Defendant C Co., Ltd. (hereinafter “Defendant C”) concluded a contract on construction works between the joint contractor (Defendant B’s share ratio of 70%, Defendant C’s share of 30%), which was the joint contractor, and the Korea hydroelectric Power Co., Ltd. on June 9, 2016 (hereinafter “instant overall construction”).

B. On September 2, 2016, the Plaintiff entered into a subcontract (hereinafter “instant construction contract”) with Defendant B and C, setting the contract amount of KRW 42,6910,000,00 and the construction period from September 12, 2016 to January 30, 2017. The Plaintiff entered into a contract for each of the following changes: (a) the contract amount on December 20, 2016; (b) KRW 44,858,000; (c) the contract amount on January 30, 2017; and (d) KRW 47,157,000 and the construction period on April 28, 2017.

C. Defendant D Co., Ltd (hereinafter “Defendant D”) entered into a subcontract with Defendant B and C on Saturdays during the entire construction of the instant case.

On May 31, 2017, the Plaintiff agreed with Defendant B and C to settle the construction amount of KRW 477,1570,000 according to the final settlement regarding the instant construction contract (hereinafter “instant settlement agreement”). Defendant B and C paid all the Plaintiff KRW 471,577,00 according to the instant settlement agreement.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 5, 6, 15, Eul evidence Nos. 1 through 3 (including provisional numbers, hereinafter the same shall apply), the purport of the whole pleadings

2. The plaintiff's assertion and judgment

A. While the Plaintiff’s assertion during the instant construction project, the Plaintiff sought payment of the above additional construction cost of KRW 111,650,000 for the said additional construction cost to Defendant B and C. However, the Plaintiff, who was faced with the financial crisis, was in accordance with the instant settlement agreement, and Defendant B and C received progress payment from the Korea hydroelectric Power Co., Ltd., the ordering person, and immediately pay the above additional construction cost.