We came across a patent filing suggesting that the Mercedes SLS AMG might get a third bodystyle. The German patent filling surfaced online through Autoblog and shows a stretched out SLS AMG with two rear-hinged demi doors and gullwing doors at the front.
The car does not have a fixed B pillar, which is most certainly going to be a challenge in terms of maintaining structural rigidity if this thing goes into production, but overall it’s an unique concept which we haven’t seen before.
These patent images could very well point to a one-off prototype, or who knows, maybe an upcoming competitor for the Aston Martin Rapide and the Porsche Panamera Turbo. 
According to the same source, Mercedes refused to shed some light on this matter by stating "We won’t take the liberty of sharing comments for any potential future products." 

Source: Autoblog