Past and present staff at the troubled Northern Rock bank could risk losing a wedge of their pension if the company goes into administration.
The scheme, which was closed to new members in 1999, has a deficit of £21.7m, though industry experts have estimated that closing it down would cost between £50m and £100m.
In this eventuality, scheme members would be put into the Pension Protection Fund, which would guarantee them at least 90 per cent of their expected pension up to £26,000.
Scheme members will be hoping for a miracle recovery, or for an organisation to buy the company whole.
One private equity group, JC Flowers, this week said it had secured £15bn which could finance a takeover, though the majority of approaches to the ailing bank have been from groups wishing to break it up.
Analysts believe the most likely outcome is that Northern Rock's unwanted assets will be put into administration, placing the bank's pension scheme in serious jeopardy.
"The conventional wisdom if you wanted to buy the assets of this business would be to let it go into administration," independent pensions expert John Ralfe told The Telegraph.
"No one would buy the company with the pension scheme if they could buy it without," he added. "Current and former employees could lose out."