A recent report said Volkswagen had not ruled it out, but correspondent Michael Zeitler reports that a move for the German giant is actually unlikely.
Amid the diesel emissions scandal, and right in the middle of F1's locked-in turbo V6 era, Zeitler said: "A foray for Volkswagen only makes sense from 2021."
And the report said Toyota and BMW, having both pulled out of F1 at the end of the 2009 season, had also dismissed rumours about launching comebacks for now.
The situation for American giant Ford, however, could be slightly different, seeing synergy with F1's new US owner Liberty Media.
Recently, a report in the Cologne newspaper Express read: "Will Ford see the new era as a chance to emulate Mercedes' advertising coup?
"'No' is the answer from Detroit," insisted correspondent Oliver Reuter.