Mining firm BHP Billiton has seen 5,000 more staff buying shares through this year's global all-employee unapproved share scheme than when its last global plan was launched in 2007.

Most of the 11,000 employees who took part in the 2007 plan opted to hold on to their shares when the scheme matured on 1 April 2010. Just 10% sold their shares after the scheme - provided by Computershare - matured. At that time, the company's share price was around £19 on the London Stock Exchange.

When the scheme opened on 2 April 2007, the share price at the close of the markets was £11.19. Staff bought about 150 shares each, which were matched by BHP Billiton, meaning the average employee holding was about 300 shares. Therefore, staff who chose to sell their total quota of shares on the London Stock Exchange made around £4,006 in profit.

Geraldine Pamphlett, share plans manager at BHP Billiton, said: "Of the 11,000 participants who got their matched shares, only 10% have elected to sell them. We are very pleased that staff obviously still feel we are a company worth investing in."

The scheme. is offered to all the firm's 35,000 staff. Each employee can spend up to $5,000 on shares, which the employer will match on a one-to-one basis after three years.

At the end of the vesting period, staff who choose to sell their shares can do so in real time on four different stock exchanges on which BHP Billiton is listed, using its online selling facility. Shares can be traded at stock exchanges in London, New York, Australia and Johannesburg.

Pamphlett said: "We recognise we have got employees all round the world and we have got our shares listed on four stock exchanges. If an employee is in Chile, it is not easy for them to then to deal in shares that are listed on the London Stock Exchange or the Australian Stock Exchange.

"When BHP Billiton matches the shares, they are kept in the nominee's account. They will stay there until the individual decides to sell them or until they cease employment with the company."

The share scheme is not tax approved, so UK employees are not entitled to a 20% discount on the option price. The firm does not take up the tax advantages available in any of the countries in which it operates to ensure the scheme is consistent globally.

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