Venture capitalists Barclays Private Equity, ABN Amro Private Equity and Exponent have all been suggested as bidders for TrinityMirror's newspapers in the Midlands.
Reports said they had made it through the first round of bidding.
Chris Bullivant, chairman of Observer Standard Media, which owns free newspapers across the region, has already declared his hand.
It is thought a fifth company may also be in the frame.
Newspapers up for sale include The Birmingham Post and Birmingham Mail.
A TrinityMirror spokesman said the group had no comment.
Following a strategic review late last year TrinityMirror decided to sell the Racing Post, the Midlands titles and interests in London and the South East.
