Here what I found in wiki
Related companies
Automobilwerk Eisenach
Isetta
Glas
Rolls-Royce Motor Cars Limited
Rover: owned by BMW from 1994 to 2000, BMW retained the Mini after selling off the rest of the company (see MG Rover Group).
Land Rover: sold to Ford; the current Range Rover was developed during BMW's ownership of the company and until recently was powered by their 4.4 L V8 petrol (gasoline) engine and BMW 3.0 L I6 diesel engine
MINI: a small hatchback; inspired by the original Mini, which was the British competitor to the Volkswagen Beetle.
Wiesmann: A company making sporty 2-seater roadsters and coupés for which BMW supplies the engine and transmission components.
Bavaria Wirtschaftsagentur GmbH: BMW Group subsidiary that offers insurance services.
AC Schnitzer: A tuning company specialising in BMW vehicles.
Alpina: A Motor Manufacturer in its own right, who creates vehicles based on BMW cars.
Breyton: A tuning manufacturer specialising in BMW cars.
G-Power: A tuning company specialising in BMW vehicles.
Hartge: A tuning company specialising in BMW, MINI and Range Rover cars.
Hamann Motorsport: A Motor Styling and Tuning Specialist who creates vehicles based on BMW cars.
MK-Motorsport: A tuning company specialising in BMW cars.
http://www.bmwgroup.com/