1. Defendant KNNN Card, Defendant A Co., Ltd., and Defendant A Co., Ltd., jointly with the Plaintiffs listed in attached Table 1.

1. Basic facts

A. Status 1 of the parties, etc.) Defendant’s national card and lot cards (hereinafter collectively referred to as “Defendant’s card companies”).

The Act on the Use and Protection of Credit Information (hereinafter “Credit Information Act”) is a company engaged in business such as credit cards, pre-paid cards, debit cards, issuance, sales, and management. Defendant A is a company established by financial institutions through joint investments.

(2) The Plaintiffs listed in Schedule 1 and 2 are those who have used or used a credit card, etc. upon entering into a contract for the use and financial transaction with one or two of the Defendant Credit Card Companies.

B. The concept of the card accident analysis system and the introduction card accident analysis system (hereinafter “FDS”) are being introduced by all domestic card companies as a system to detect abnormal transactions or fraudulent use due to the theft, loss, forgery, etc. of credit cards.

According to the FDS, a large amount of card use information and customer information based on the past accident transactions created an analysis model in accordance with statistical techniques, based on this, and based on the results, the card company will refuse to approve the card if it is discovered for any abnormal transaction due to an accident pattern analyzed at the time of using the credit card.

C. Defendant’s national card’s customer information leakage 1) concluded a FDS development service contract and whether to provide card customer information) Defendant’s national card was necessary after the introduction of FDS for the first time in 2008, and entered into a purchase contract with Defendant A on January 30, 2013.

B. The development human resources of Defendant A, including the project general manager B, engaged in the development of FDS from February 2013 to August 2013, and among them ① from February 2013 to March 2013, Seoul.