This excerpt taken from the BP 20-F filed Mar 6, 2007.
Plans for executive directors
Executive Directors Incentive Plan (EDIP) share element (2005 onwards)
An equity-settled incentive share plan for executive directors driven by one performance measure over a three-year performance period. The award of shares is determined by comparing BPs total shareholder return (TSR) against the other oil majors. In addition, for the group chief executive, 27% of the grant is based on long-term leadership (LTL) measures. After the performance period, the shares which vest (net of tax) are then subject to a three-year retention period. The directors remuneration report on pages 61-68 includes full details of this plan.
Incentive Plan (EDIP) share element (pre-2005)
Incentive Plan (EDIP) share option element (pre-2005)