2. Defendant A.

Defendant A Co., Ltd. (hereinafter “Defendant A”) is a company engaged in business such as credit cards, pre-paid cards, debit cards, issuance, sale and management, etc., and Defendant B Co., Ltd. (hereinafter “Defendant B”) is a company established by joint investment by financial institutions, which is engaged in business such as credit inquiry and credit investigation as prescribed by the Act on the Use and Protection of Credit Information.

[Attachment 1] List of Plaintiffs is the list of all Plaintiffs. Of the Plaintiffs’ lawsuits, where the lawsuit is unlawful, it is classified as the list of Plaintiffs 2; where the card customer information was leaked on April 2010 and December 2013, the list of Plaintiffs 3; and where only the card customer information was leaked on December 2013, it is classified as the list of Plaintiffs 4; and where there is no evidence to acknowledge that the card customer information was leaked, it is classified as the list of Plaintiffs 5, respectively.

It is a person who has used or used a credit card, etc. under the credit card, etc. after concluding a contract for use and financial transaction with Defendant A.

The concept of the card accident analysis system and the introduction card accident analysis system ("FDS") are introduced by all domestic credit card companies as a system to detect abnormal or fraudulent use due to theft, loss, forgery, etc. of credit cards. According to FDS, it is possible to establish an analysis model based on statistical techniques by utilizing large amount of card use information and relevant card customer information based on past accident transactions, and based on this, if it is discovered that abnormal types of transactions have occurred according to the statistical analysis pattern, it is possible to reject the card approval.

Defendant A’s entering into a contract for the development of FDS and providing card customer information, around 2006, Defendant A introduced FDS to implement a regular new e-mail, and thereafter, C or B.