By: Jordan Valinsky, CNN Business (CNN) -- Marriott says its guest reservation system has been hacked, potentially exposing the personal information of approximately 500 million guests.

Marriott International says a guest reservation database has been breached and may have exposed information of approximately 500 million guests.

Marriott International says a guest reservation database has been breached and may have exposed information of approximately 500 million guests. The company says it is investigating and addressing ...

Marriott was an early adopter of mobile when its optimized site debuted in 2008. Ten months after adding booking features to the site, the company reportedly grossed $1.25 million in revenue (see ...

Marriott International says a guest reservation database has been breached and may have exposed information of approximately 500 million guests.

Marriott International says a guest reservation database has been breached and may have exposed information of approximately 500 million guests. The company says it is investigating and addressing ...