Friday is the last day for prospective bidders to lay their cards on the table and make an offer for the ailing lender.
Both the Virgin Group and JC Flowers have done so in the weeks since the bank revealed it was in crisis, with US firm Cerberus and former Abbey boss Luqman Arnold also rumoured to be waiting in the wings.
Three possible outcomes have been highlighted by the BBC's business editor, Robert Peston, which are:
- The sale of the whole company
- The sale of the basic physical infrastructure of the business i.e. the branches, information technology and call centre, which may also include Northern Rock's £13.5bn of retail deposits and matching assets
- The sale of the infrastructure plus all those securitised mortgages
