1. The plaintiff's appeal is dismissed.

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

The purport of the claim and appeal is the purport of the appeal.

1. Basic facts

A. On August 17, 2015, the Defendant was awarded a contract with the Korea Rural Community Corporation (the Governor of the Jeonnam Regional Headquarters) for the construction of “B” (hereinafter “B”) from the cost of the instant construction (including value-added tax; hereinafter the same shall apply) to KRW 2,971,335,000 (including value-added tax; hereinafter the same shall apply) and from August 21, 2015 to November 30, 2015.

On November 25, 2015, the Defendant and the Korea Rural Community Corporation entered into a contract to change the construction work that increases the construction amount to KRW 3,403,923,00 and extends the construction period to December 28, 2015.

Contract amount: Construction period of KRW 2,624,60,00 (i.e., supply price of KRW 2,386,00,000, value-added tax of KRW 238,600,000): From the commencement date of construction: Within three days from the commencement date of construction: Price adjustment and payment following changes in payment, changes in economic conditions, etc. in proportion to the same ratio as that received from the project owner; ① Price adjustment and payment according to the same ratio within three days from the date of adjustment from the date of receipt by the project owner; and ② Contract bond for payment within three days from the date of receipt by the project owner: 238,60,000 (10% of the supply price)

B. On August 24, 2015, the Defendant: (a) prepared a service contract for the supply of geothermal goods and a service contract (hereinafter “instant service contract”) stating that the instant construction work is subcontracted en bloc; (b) delivered to the Plaintiff (Provided, That the beneficiary was not written); and (c) the main contents are as follows.

다. 피고는 2015. 8. 26.경 이 사건 용역계약서의 계약금액과 계약보증금을 아래와 같이 변경하고 수급자를 원고로 기재한 수정 용역계약서를 작성하여 원고에게 교부하였는데, 원고는 그 무렵 위 수정 용역계약서의 수급자란에 원고의 도장을 날인한 후 이를 계약금액: 1,100,000,000원(= 공급가액 1,000,000,000원 부가가치세 100,000,000원) ★ 한국농어촌공사와 발주자의 계약 총금액 중 나머지도 90%로 추가 별도 계약함 계약보증금: 110,000,000원(공급가액의 10%) 다시 피고에게 교부하였다....