Former Rangers chairman Alastair Johnston has joined fans groups in urging transparency among all the four groups bidding to take over the club.
Johnston's preference is for the Blue Knights consortium led by former Rangers director Paul Murray.
But consortia from Germany, the United States and Singapore also submitted "best and final offers".
"They need to be transparent about who the individuals are, who are part of the consortiums," said Johnston.
Administrator Duff & Phelps hopes to assess the four proposals in the coming days, with a preferred bidder being chosen next week with a view to a new owner being in place before the end of the season.
But Johnston, who had opposed the ill-fated sale by Sir David Murray to Craig Whyte in May as he doubted the present owner's credentials, hopes the same mistakes will be avoided this time round.
He says Rangers fans must be told "what the resources are and what their plans are for the club and how they are, on the record, going to handle and manage".
"The word consortium is a useful phrase, but it disguises a whole lot of mischief potential and I think that, this time round, Rangers fans need to be told," said Johnston.
Sale Sharks owner Brian Kennedy decided against making a bid by Wednesday's deadline, although he could change that position to prevent a preferred bidder putting the club into liquidation instead of agreeing a company voluntary arrangement (CVA).
That leaves the Blue Knights bid, which would involve Ticketus, the company to whom Whyte sold several seasons of future season ticket sales in order to finance his own takeover, as the most public bidder.
"The Blue Knights ticks several boxes," said Johnston. "One, because they have the faculty of dealing with Ticketus, which is either part of the solution or part of the problem.
"Paul Murray certainly knows what he's getting into with respect of the club.
"They are fully disclosed as to who they are and who the other investors are and the transparency will be there.
"I think the fans at least know what they are getting into and this, at the end of the day, appears to be supported by a broad universe of the Rangers fans and that's really important.
"That's the most important thing of all."
Rangers Supporters Assembly president Andy Kerr also appealed to the administrator to let Rangers fans know who has made a bid and on what basis.
"We know all about the Blue Knights, they are the only ones with any detail, and we know about Brian Kennedy, who seems to be a backstop if all goes wrong, but we don't know enough or anything about the other bids," he said.
"So we would like the answer to basic questions: who are you and why do you want to buy Rangers?
"We want to know who is bidding to get the club out on a CVA and who wants to liquidate.
"We would like to have a discussion about their plans."