"We want to make sure there is a formula one race in Germany every year in the future," said Ecclestone.
The 83-year-old Briton said at the time that there are "one or two other interested parties", and the Rhein newspaper now claims they are entities from Dusseldorf and the US, and a private equity firm.
Correspondent Dietmar Bruck said the parties all have until Monday to submit their final proposals, with Ecclestone apparently no longer in the running.
Meanwhile, Britain's Guardian newspaper claims the newly-retired former Mercedes boss Ross Brawn was approached to take over from Ecclestone, should the F1 chief executive lose his job amid the corruption affair.
Adding that F1 owners CVC refused to comment, correspondent Richard Williams said the approach to Brawn had been "unsuccessful".