CG56341 - Shares and securities: employee share schemes: employment-related securities: employee: restricted securities example
Share value lower than when recieved
The effect of the  rules and  can be to create a larger loss for Capital Gains Tax purposes than would otherwise be the case.
Y receives 1,000 shares in his employing company. Their initial actual market value was agreed at 70p per share and the unrestricted market value was £1 per share. He did not sign an election.
When the restriction is lifted the shares' market value is now only 60p per share - less than when Y received them.
The amount which constitutes earnings of Y on acquisition is based on 70% of the unrestricted market value (70% of £1 = 70p),
when the restrictions are removed the amount which counts as income of Y is 30% of whatever the market value is at that time (30% of 60p = 18p)
So, if Y immediately sells the shares for 60p per share, the difference between the market value on acquisition, £700, and the sale proceeds is £100. But overall Y has employment income £880 and there is an allowable capital loss of £280.