1. Basic facts

A. On August 13, 2012, the Defendant entered into a contract with the Plaintiff for the construction work of the explosive line from the Korea Rail Network Authority to the end of August 13, 2012, and agreed to adjust the portion of the construction work of the said new construction work (hereinafter “instant construction work”) to the Plaintiff within KRW 726,880,00 (including value-added tax) and the construction period from August 13, 2012 to June 24, 2013. However, in relation to the construction work, the Defendant paid KRW 198,00,000 in advance, and paid KRW 198,00 in advance once a month as progress payment, and in case of a design change, economic situation change, etc., the Defendant agreed to adjust according to its content and proportion within 30 days from the date of adjustment by the Korea Rail Network Authority.

(hereinafter “instant subcontract”). (b)

On August 23, 2012, the Plaintiff received 198,000,000 won as advance payment from the Defendant. Since then, the Plaintiff claimed 64,790,000 won as the first progress payment for October 2012, and subsequently, 25,916,000 won as advance payment was decided to settle the remainder of 38,874,000 won, and claimed 252,90,000 won as the second progress payment for November 2012, and received 101,20,000 won as advance payment and received the remainder of 151,70,000 won.

C. On December 28, 2012, the Plaintiff filed a claim against the Defendant for the payment of KRW 162,00,000 (including value-added tax) for the progress payment for December 28, 2012. Since then, the Plaintiff and the Defendant filed a claim on January 7, 2013 for the payment of KRW 162,00,00 (including value-added tax) with the Defendant. On January 7, 2013, the Plaintiff and the Defendant changed the existing design drawings according to the need for design change and constructed accordingly, (i) new waterway concrete construction, (ii) upper line retaining wall construction, (iii) upper line base destruction (including expenses for installing earth walls), (iv) upper line platform for the protection of gravel (including expenses for installing earth walls), and (v) lower ground destruction (including expenses for installing earth walls), (vii) existing non-permanent retaining wall cutting works, and (viii) existing drainage pipe construction works, and (i) existing drainage pipe construction works, and (iv) existing drainage pipe construction works.