1. All appeals filed by the Defendant Intervenor are dismissed.

2. The costs of appeal shall be borne by the Defendant Intervenor.

1. The reasoning for the court's explanation of this case is as follows, except for the addition of the following between "(11)" and "(2)" to the judgment of the court of first instance, and therefore, it is like the entry of the reasons for the judgment of the court of first instance in accordance with the main sentence of Article 420 of the Civil Procedure Act.

In addition, the instant supply contract provides for the delivery of goods by the Defendant’s Intervenor B as a prior performance obligation. Therefore, in order to hold the Plaintiff liable for nonperformance, the Defendant’s Intervenor B shall be deemed to have provided lawful performance or the Plaintiff’s intent to refuse to accept the payment is apparent.

However, as seen earlier, it cannot be deemed that the Plaintiff clearly expressed his/her intent to refuse to accept the goods, there is no evidence to acknowledge that the Intervenor B performed his/her duty to supply the goods to the Plaintiff after the agreement on July 5, 2011.

2. In conclusion, the plaintiff's claim is accepted within the above scope of recognition, and the remaining claims are dismissed as there is no ground. The judgment of the court of first instance is just in conclusion, and all appeals of the defendant joining the defendant are dismissed. It is so decided as per Disposition.