Employees at Lloyd's insurer Cox, who are members of the company's share incentive scheme, received more bad news when the 1997 scheme matured last month.

The option price at which they could have purchased shares in their company was 110p, while Cox's share price was at one point trading as low as 32p.

The blow follows Cox's decision earlier this year to close its final salary pension scheme - a defined benefits scheme - in favour of an alternative that would give the company more flexibility.

An employee, who wished to remain anonymous, said: "This is a double whammy... There's nothing you can do because shares are at below half the option price."

Cox chief executive Michael Dawson said, although employees would not be able to realise the expected gains, they had not lost any money because they had received their full savings with interest.

He said they could buy shares on the open market at the lower price if they wanted.

"I think it's important in any share scheme that you think of the long-term value of a business."

He said in this scenario the most important thing was that people had the choice on whether they invested or received their savings back.