Originally Posted by Fortbimmer
The shark fin is standard and probably a multipurpose antenna for AM/FM/Sat and GPS.
This is the most logical as well as correct answer from what I've read and asked at my dealer. Explain why BMW would go through the trouble of designing the fin just to have it for the sat radio and have the am/fm and gps inbeded in the rear window? All of the above functions are or should be ran though the fin. Just for sat radio would be dumb.