A. The plaintiff is a corporation established for the main purpose of the performance planning business, etc., and the defendant is a regional housing association organized for the purpose of carrying out a housing construction project in the Nam-gu Seoul metropolitan District under the Act on the Maintenance

B. On May 9, 2016, the Plaintiff concluded a contract on vicarious execution for the production of advertising materials and advertising request for the apartment sales advertisement of B-house housing association (hereinafter “instant contract”) with the Committee for Promotion of the Regional Housing Association and its agency company D (hereinafter “D”) (including value-added tax) from May 9, 2016 to November 15, 2016, with the service period as the service cost of KRW 1135 million (including value-added tax).

C. The Defendant succeeded to all rights and duties of the promotion committee of the regional housing association B under the instant contract to the Plaintiff.

As the service cost of the instant contract, the regional housing association promotion committee paid to the Plaintiff KRW 220,917,000 as a sum between June 9, 2016 and November 29, 2016, and D, an agent of which paid KRW 80,00,00 to the Plaintiff via E, via the stock company, KRW 80,000,000,000,000 on May 16, 2016, and KRW 18,000,000,000 on July 26, 2016.

[Reasons for Recognition] Evidence No. 1, Evidence No. 2-1, Evidence No. 2, Evidence No. 6, Evidence No. 7-2, and the purport of the whole pleadings

2. The parties' assertion

A. The Plaintiff performed all the duty of service, such as advertising for selling apartment units in the district housing association B under the instant contract, but the Defendant paid only KRW 220,917,00 as the service cost of the instant contract to the Plaintiff.

Therefore, the defendant is obligated to pay the plaintiff the service price of KRW 914,093,00 and the delay damages.

B. Defendant 1) The Plaintiff failed to complete the performance of its service obligations under the instant contract. 2) The Plaintiff sent a written claim to the Defendant requesting payment of KRW 477,382,050 on January 17, 2019, and the Plaintiff and the Defendant around February 2019, based on the said written claim.