The plaintiff is a company established for the purpose of the construction design business and the construction supervision business, and the defendant is a company that has been entrusted with land and engages in the construction business to achieve the purpose of the trust.

On February 13, 2012, the Defendant obtained the approval of the housing construction project plan with the purport that the 808 household units with 14-24 apartment units of the 10-24th floor above the ground will be newly built from the Namyang-si market to the total project cost of 253,704,440,000 and the construction period of 15-7, 2014 from May 15, 2012 to July 14, 2014, and the remaining Yangyang-ju market designated the Plaintiff as a supervisor of the said apartment construction (hereinafter “instant construction”) on May 7, 2012, and notified the Plaintiff thereof.

Accordingly, on May 17, 2012, the Plaintiff entered into a supervision service agreement with the Defendant on the instant construction project (hereinafter “instant supervision service agreement”) and set the total amount of supervision fees to KRW 2,003,293,569 (including surtax), and received advance payment of KRW 99,00,000 (including surtax).

The main contents of the instant supervision service contract and the terms and conditions of the supervision service contract are as follows.

The scheduled commencement date and the scheduled commencement date of supervision services: The contract period: From May 2012 to July 2014, Article 1 of the Terms and Conditions of the Housing Construction Supervision Services Contract (General Provisions) of the same Act shall determine matters concerning the rights and obligations between the project operator and the consulting engineers as the consulting engineers are able to perform the supervisory duties in accordance with the detailed standards, etc. of housing construction supervision prescribed by Article 24 of the Housing Act and the Ministry of Land, Transport and Maritime Affairs (hereinafter referred to as the "business standards").

Article 3 (Supervision Services) (1) A supervisor shall perform basic duties and perform special duties at the request of a project proprietor, as prescribed by the terms and conditions of the contract for housing construction work supervision services.

(2) The term "basic duties" means the following duties:

1. Examining the propriety of the construction plan, the process schedule and design documents;