A. 1) The Plaintiff is a company established on August 12, 2013 for the main purpose of civil engineering and construction business, etc., and the Defendant C is a company incorporated on May 11, 2018 to the Defendant (Co., Ltd.). The Defendant C is a “Defendant,” regardless of whether there is a mutual change before and after the mutual change. D is a company established on June 14, 2007 for the main purpose of construction business, etc. 2) D was working as the Defendant’s representative director from March 13, 2012 to March 13, 2018, and E was working as the Defendant’s representative director from August 18, 2013 to August 18, 2016; and F was employed as each of the Defendant’s inside directors from March 13, 2015 to May 11, 2017.

B. 1) On August 24, 2015, the Defendant concluded a subcontract agreement with the Plaintiff as to KRW 770,000,000 for the construction cost (including value-added tax) and the construction period from August 25, 2015 to November 30, 2015, each of which is newly constructed on the G ground of Yangsan-si (hereinafter “instant H factory”).

2) The subcontracting of the water plant project (hereinafter referred to as the “instant H plant subcontract”).

2) The lower court determined that the instant H factory subcontract agreement was the content of the instant H factory subcontract and the main contents of the general terms and conditions of the instant construction contract are as follows (hereinafter “instant H factory subcontract agreement”).

A) The term “instant special agreement” (hereinafter referred to as “instant special agreement”).

(A) “A” (the defendant; hereinafter the same shall apply) in the event of a design change or recognition and alteration of an additional construction project with the ordering authority under Article 7 (Modification of Design).

) and “B” (the plaintiff, hereinafter the same shall apply)

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