LY Corporation

Japan's Ministry of Internal Affairs and Communications issued written administrative guidance to LY Corporation on July 31, 2026 after finding that Treenod Inc., the LY subsidiary that operates the 'LINE Games' app, transmitted user identifiers (MIDs) and specified user information from users' devices to a third-party data analytics provider for ad-effectiveness analysis, without LY's internal approval and without giving users the opportunity to confirm what information would be sent, its purpose, or its recipient. The transmissions ran from May 25, 2022 to April 3, 2026, totaling approximately 8.03 million instances, about 7.52 million of them involving Japanese users. The ministry found the conduct violated Articles 27-5 and 27-12 of Japan's Telecommunications Business Act, which govern management of specified user information and external transmission notice requirements.

In October 2023, LY Corporation suffered a data breach when hackers accessed systems through affiliate NAVER Cloud. The breach leaked 440,000+ items of personal data including users' age group, gender, and service histories. The incident stemmed from shared Active Directory authentication with former parent company Naver. Japan's Ministry of Internal Affairs issued administrative guidance twice in 2024, calling for system separation from Naver.