The future generation 2013 Maserati Quattroporte was spied recently while doing some test runs on the Nurburgring racetrack in Germany. Unfortunately, the 2013 Quattroporte prototype caught on camera is heavily camouflaged. We guess Maserati is still trying to keep its general proportions a secret. Maserati will probably unveil the new Quattroporte (2013) towards the end of this year, or at the beginning of the next one. We'll have more details about the 2013 Quattroporte as soon as they're available.