South Korea's National Tax Service (NTS) has launched audits of 50 companies suspected of serious tax irregularities involving 1.9 trillion won ($1.4 billion), after reviewing 2,639 high-value corporate-owned homes. Controlling shareholders and their families lived in or privately used 1,097 homes, or 42%, after 1,157 rental properties and 385 homes used for business purposes were excluded. The first-phase targets include 28 owner-family residences, five real estate speculation cases and 17 luxury villa-use cases. The NTS is examining arrangements including a 20 billion won ($14.4 million) Hannam-dong mansion and luxury retreats presented as employee welfare facilities. Investigators will use account inquiries and digital forensics to determine whether company funds increased owner-family wealth, while later audits may cover overseas company housing and support for owners' children's overseas study.