1. The plaintiff's claim is dismissed.

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

1. Basic facts

A. The Plaintiff is engaged in the manufacture and installation of machinery and steel structure after completing business registration with the trade name of “C”. The Defendant is engaged in the industrial machinery and steel structure water supply and drainage facility business under the trade name of “D”.

B. On April 17, 2015, the Defendant entered into a contract with the Defendant on the terms of contract for the production and installation of machinery and pipes, and for the installation and installation of reports on Group, among the production and installation works, between the Defendant and Nonparty N&C Co., Ltd. (hereinafter “N&C”), with the contract period of KRW 830,000,000 and the contract period of April 17, 2015 to September 30, 2015.

C. On April 29, 2015, the Plaintiff entered into a contract with the Defendant to enter into a contract with the F Corporation (hereinafter “instant construction contract”) under which the contract amount is KRW 425,00,000 (excluding value-added tax) for the construction cost, and the contract period is from April 29, 2015 to October 30, 2015, which is determined as the period from April 29, 2015 as a result of the on-site civil engineering process and at the time of a change in the schedule of the original Agency (hereinafter “instant construction contract”).

At the time of the instant construction contract, main materials, such as pipes, other equipment, etc., are supplied from Tech C&C, and subsidiary materials, such as gas diskettes, and V, are supplied by the Defendant, and the Plaintiff was in charge of installation.

The Plaintiff’s progress of the instant construction works but the supply of materials does not facilitate. Ultimately, the progress of the construction works was discontinued on March 2016, and the Defendant paid KRW 310,659,32 to the Plaintiff totaling KRW 310,659,322 as the construction cost of the instant case.

E. Meanwhile, during the construction period, the Defendant continued to request K&C, the prime contractor, to increase the construction amount due to the smooth supply of materials and the delay of construction, but the consultation was not well achieved. On April 26, 2016, after the discontinuance of construction, N&C should pay KRW 150,000 to the Defendant.