Facebook founder Mark Zuckerberg and his pediatrician wife Priscilla Chanhave bought a waterfront mansion in Miami that’s still under construction — sources told Gimme Shelter exclusively.

The property on ultra-exclusive Indian Creek Island, otherwise known as ‘Billionaire Bunker,’ was on the market for $200 million. The price that Zuckerberg and Chan agreed to pay: a colossal $170 million.

A message seeking comment from Zuckerberg was not returned by press time.