The following facts may be acknowledged if there is no dispute between the parties, or if Gap evidence 1, Gap evidence 2-1, 2, 3, 5, Eul evidence 2-1 to 8, and Eul evidence 2-1 to 2-8, and the purport of the whole pleadings is shown in the witness Eul's testimony:

The plaintiff has operated a business manufacturing industrial machinery in the trade name of "C".

On December 27, 2011, the Plaintiff entered into a contract with D (hereinafter referred to as “D”) on the terms of manufacturing and installing a high-performance greenhouse gas drieder (hereinafter referred to as “instant dryer”) at KRW 453,500,000 (excluding value-added tax) by February 2012 (hereinafter referred to as “instant contract”).

After that, the Plaintiff received KRW 349,195,00 in total from D, KRW 149,540,00 in advance and intermediate payment of KRW 149,65,00 in accordance with the instant contract.

On March 12, 2012, the Plaintiff manufactured the instant drying machine and was conducting a trial operation for the said drying machine, but failed to meet the mechanical performance required by D, and thereafter, the Plaintiff continued to perform a total of 6-7 times trial operation until April 13, 2012, but failed to meet the mechanical performance required by D.

D, on May 24, 2012, notified the Plaintiff of the rescission of the instant contract and demanded the return of KRW 349,195,00 in total of the advance payment and intermediate payment.

On June 7, 2012, the Plaintiff requested D to supplement the drying machine of this case and revise the terms and conditions of the instant contract. However, D rejected the Plaintiff’s request.

D was merged with the Defendant on July 1, 2012.

On November 26, 2012, the Plaintiff recognized that the instant contract was lawfully rescinded under mutual agreement due to the difference between the Defendant’s demand and the construction period produced by the Plaintiff to the Defendant, and accordingly, KRW 349,195,00 in total received from the Defendant.