Now That's a Big Boat
Ironically, though part of a yacht’s appeal stems from the privacy it offers its owner, very large yachts (in excess of 299 gigatons) are required by the International Maritime Organization to publicly transmit their location at all times via an Automatic Identification System transponder. (You can see the current location of all such yachts—and other very heavy boats—at marinetraffic.com.)
That's about 4 million times the mass of a Nimitz class aircraft carrier. I guess you need a big boat if you are going to land your private A 380 on it.