This excerpt taken from the HSY DEF 14A filed Mar 16, 2007.
What are the effects of a change in control?
Upon a change in control of Hershey, all outstanding stock options and SARs and all restricted stock unit and restricted stock awards will fully vest, unless the Committee provided otherwise in the award agreement. The effect of a change in control on performance-based and other awards will be as the Committee determines.
Currently, a change in control will occur if: