In September, Marriott International received an alert from an internal security tool regarding an attempt to access the Starwood guest reservation database. Marriott learned during the investigation that there had been unauthorized access to the Starwood network, which had occurred since 2014.

After receiving the internal security alert, Marriott engaged leading security experts to help determine what occurred. They installed additional security tools to help gather facts and reported the incident to law enforcement. Their internal and external security teams have been working nonstop to investigate the incident, implement additional security measures, and address what was found.