The judgment below is reversed and the case is remanded to Seoul High Court.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. Article 19(1) of the Monopoly Regulation and Fair Trade Act (hereinafter “Fair Trade Act”) prohibits “agreement on acts that unfairly restrict competition”. The agreement includes not only explicit agreement but also implied agreement.

In this context, the essence of the agreement lies in the communication between two or more enterprisers, so it cannot be found that there was an agreement as a matter of course on the ground that there was an appearance consistent with the act listed in any of the subparagraphs of the above provision, but it can be deemed that there was an agreement in a case where a circumstance to prove the reciprocity of the communication between enterprisers exists

(See Supreme Court Decision 2012Du17421 Decided November 28, 2013 (see, e.g., Supreme Court Decision 2012Du17421, Nov. 28, 2013). In a case where competitors exchange information on major competitive factors, such as prices, the exchange of such information may be a means to facilitate or facilitate collusion by eliminating uncertainty in the decision-making process, such as price determination, and thus, it may serve as a valuable material to recognize the reciprocity of the communication among business entities. However, even so, it cannot be readily concluded that there exists an agreement on an act unfairly restricting competition solely on the information exchange. Determination of whether there exists such an agreement should be made by comprehensively taking into account all the circumstances, such as the structure and characteristics of the relevant market, the nature of the exchanged information, the subject and time and method of the information exchange, the purpose and intent of the exchange, the degree of difference in the external form and degree of difference between business entities, such as the price calculating volume after the information exchange

(See Supreme Court Decision 2013Du16951 Decided July 24, 2014). 2. The lower court determined as follows.