It is not so much a deadline as a filtering exercise by Rangers' administrators, Duff & Phelps.

Asking all the interested parties to provide proof of funding and to submit indicative offers for the club by today is an attempt to identify those with serious intentions and backing. The uncertainty about Rangers' future is still several weeks, and many significant decisions, away from being resolved. Any progress that is made tends to be painstaking, and an indication only of further complexities.

Even the offers themselves will be conditional on a number of issues. The purpose for the administrators is to begin the process of formulating a company voluntary arrangement (CVA) to offer to the club's creditors, with those holding 75% of the total debt needing to vote in favour for the CVA to pass. Any fee received for the sale of the club will be used to fund this. Yet Craig Whyte remains the owner of Rangers, even if Duff & Phelps believe that there is a legal mechanism they can use to take control of his shareholding. Several financial sources believe this to be far from certain.

The administrators are more bullish that Whyte can no longer be the secured creditor, but he could still challenge that. The issues are well-established, but several outcomes remain possible. It is in Duff & Phelps' interests for several interested parties to lodge indicative bids today, since their two primary roles are to stabilise the business and generate as high a return as possible for creditors. They will want to encourage a contest, and there seemed a pointed message in Paul Clark's comments last week that he doesn't "care how many bidders we end up with but I want to know who they are, what their worth is, so then we have more serious conversations about achieving new ownership. The problem we have got [is] one or two parties are prepared to talk to the media and other parties have been quietly and diligently getting on with their business behind closed doors".

Five potential bidders have been identified: Brian Kennedy, the multi-millionaire owner of Sale Sharks, Paul Murray and his Blue Knights consortium, Fortress, a New York-based investment bank, Shazad Bakhsh, a Glasgow-based Singaporean businessman, and Club 9 Sports, a Chicago-based company that failed in bids for Tranmere Rovers and Sheffield Wednesday. The obligation for Rangers' administrators is to choose the bid that represents the best deal for the creditors, but even that is not straightforward.

If Whyte is confirmed as no longer being the secured creditor, and a judgment is reached that doesn't leave Ticketus as among the creditors, then Her Majesty's Revenue and Customs will be the dominant figure in the CVA decision. The Revenue are currently owed £15m – a combination of the £9m in unpaid PAYE and VAT run up by Whyte and the wee tax case that was uncovered during the takeover process – and would hold 75% of the total debt, meaning their vote alone will decide the outcome.

The administrators have also maintained from the outset that the CVA will take into account the verdict of the first tier tax tribunal into Rangers' use of Employee Benefit Trusts from 2001 to 2010, which is expected next month and could deliver a bill of up to £50m to the Ibrox club. This would further enhance HMRC as the dominant creditors, and influence any decision they take on accepting a CVA. The move to identify the serious bidders by today's deadline will also allow the administrators and HMRC to begin discussions on what value might be acceptable to the tax man.

Finance will not be the only consideration. HMRC face a choice between recouping as much money as possible for tax payers – which normally means a CVA since a liquidation tends to see assets sold at below value – or to be seen to punish the club if the tribunal finds Rangers guilty of tax evasion. In the former case, HMRC will want to be assured that the new owners will run the club with good corporate governance.

As Leeds United and Portsmouth have found to their cost, a club in administration is often considered something to be exploited by people looking to earn a quick profit. Football is seldom, if ever, able to deliver that kind of return, and both clubs struggled to achieve stability again, with Portsmouth currently back in administration. Rangers are vulnerable, and those with experience in football club sales suggest that the most common buyer is somebody with an emotional link to the team.

Murray's Blue Knights group is composed of Rangers supporters, and the plan is to run a share issue that allows ordinary fans to have a role in the running of the club. The deal requires Murray's consortium to borrow money from Ticketus to fund the purchase, whereas Kennedy is independently wealthy enough to fund his own takeover. Yet he describes himself as a "reluctant" bidder, who expects to lose out and is motivated only by not wanting to see the club go out of business, even although he is a Hibernian supporter.

The pessimism seems strange in an individual who is used to making bold decisions in his business career, and who is mostly always rewarded by them. He has also spoken to his long-time friend, Graeme Souness, about the club, and met Ally McCoist, the Ibrox manager, which is a commitment from somebody who has said he will step aside for the Blue Knights.

Even setting a deadline removes few of the uncertainties around Rangers' circumstances.