1. The Defendant’s KRW 22,920,191 as well as the Plaintiff’s KRW 6% per annum from August 26, 2015 to June 24, 2016.

1. Basic facts

A. The Plaintiff is a company whose business purpose is to manufacture and sell information and communications equipment and monitoring equipment, and the Defendant is an information and communications construction business, etc.

B. On October 2012, the construction of the Defendant and the limited liability company entered into a contract with the Korea Rail Network Authority for the construction of the three tools for the installation of the three sections for the instant construction works on the tracks of the high-speed rail (hereinafter “instant construction”) (hereinafter “instant construction contract”) and set the deadline for the completion of the construction as December 31, 2014.

C. On July 17, 2014, the Plaintiff entered into a contract for the supply and installation of optical image transmission equipment (hereinafter “instant installation contract”) with the Defendant, and the term of the contract was from July 17, 2014 to December 31, 2014; the contract amount was KRW 2,183,060,00 (supply price of KRW 1,984,60,600 and value of KRW 198,460,00), and the advance payment was 30% of the contract amount (654,918,000), the intermediate payment was 20% of the contract amount (436,612,000,000) of the contract amount after the completion of the factory inspection; and the remainder was 20% of the contract amount (436,616,000,0000,000 won); and the contract amount was 30% of the contract amount after completion inspection (the remainder was 36,001,5400.5).

After that, the problems arise that the Plaintiff is expected to install the optical image transmission facilities (transmission) and other companies in another construction section, which are expected to be installed in the said 3 construction section, and the luminous transmission facilities (receiving facilities) were determined to be installed as equipment of eti, a stock company (hereinafter referred to as “UT”), which is not the Plaintiff’s equipment, at the conference related to the optical image transmission facilities (hereinafter referred to as “UT”), on August 19, 2014 through several meetings among the construction parties.

E. Accordingly, on October 27, 2014, the Plaintiff entered into a contract for the supply and installation of goods with Korea Communications Co., Ltd. (hereinafter “Korea Communications Corporation”) (hereinafter “instant contract for the installation of UT Equipment”), and determined the amount of supply in KRW 272,70,000 (Additional Tax).