1. The plaintiff's claim is dismissed.

2. The costs of the lawsuit, including costs incurred by participation, are all assessed against the Plaintiff.

1. Basic facts

A. A. Around January 2014, the Defendant Intervenor requested the Defendant to purchase fiberss related to “the construction of an urban facility in the Gangdong-gu River” (hereinafter “instant facilities”). On May 2, 2014, the Defendant entered into a contract for the supply of goods (hereinafter “instant supply contract”) with the Plaintiff. The main contents of the instant supply contract are as follows.

Contracting Method: Negotiated contract title: The name of goods to be purchased from the textile of the construction site of the city facilities in the Kimpo-han River: The time limit for air leisure and the delivery: August 31, 2016: The Defendant’s supplementary intervenor’s penalty for delay: 0.150%: the Defendant’s supplementary intervenor’s Incheon Regional Headquarters: the end-user’s inspection agency: The delivery condition for the end-user: the delivery place: the method of payment within the field of the construction site of the city facilities in the Kimpo-m

B. Although the delivery period of the instant supply contract was June 30, 2014, the Plaintiff, the Defendant, and the Defendant’s Intervenor agreed to extend the delivery period in sequence on June 30, 2015 and December 31, 2015.

C. On January 19, 2015, the Plaintiff supplied the instant leisure machine at the place of supply, and the Defendant Intervenor paid a part of the price of the goods as progress payment on March 3, 2015.

After the delivery of the instant leisure machine as above, from August 2015 to November 1 of the same year, the Plaintiff was driven through a trial from August 2015 to the end of the same year. On November 13, 2011 of the same year, the Defendant Intervenor notified the Plaintiff that the Plaintiff take fundamental measures regarding the Plaintiff, on the grounds that the Plaintiff’s failure to perform performance, such as the occurrence of melting of the inside fiber plates of the filtering machine, the internal fiber plate of the filtering machine, the occurrence of V melt, and the deterioration of water quality, etc., occurred.

E. On February 19, 2016, the Plaintiff submitted a plan to take measures to supplement the Defendant’s Intervenor’s demand for supplement, and the same year.

22. The delivery period to the intervenor joining the defendant:

5.15. Requests the extension of the period to 15. The defendant's assistant intervenor.