https://www.theregister.co.uk/2018/11/30/marriott_starwood_hotels_500m_customer_records_hacked/

US hotel chain Marriott has admitted that a breach of its Starwood subsidiary's guest reservation network has exposed the entire database – all 500 million guest bookings over four years, making this one of the biggest hacks of an individual org ever.

"On September 8, 2018, Marriott received an alert from an internal security tool regarding an attempt to access the Starwood guest reservation database in the United States," said the firm in a statement issued this morning. "Marriott learned during the investigation that there had been unauthorized access to the Starwood network since 2014."