This excerpt taken from the VRSN DEF 14A filed Jul 27, 2007.
The Purchase Plan imposes certain limitations upon a participants rights to acquire common stock, including the following limitations:
Purchase rights may not be granted to any individual who owns stock, including stock purchasable under any outstanding purchase rights, possessing 5% or more of the
total combined voting power or value of all classes of stock of VeriSign or any of its affiliates.
Purchase rights granted to a participant may not permit the individual to accrue the right to purchase our common stock at an annual rate of more than $25,000,
valued at the time each purchase right is granted.
If on a purchase date the fair market value of a share of our common stock is less than half of 85% of the fair market value of a share of our common stock on the
offering date, then on such purchase date no participant may purchase more than the number of shares determined by dividing 85% of the fair market value of a share of our common stock on the offering date into 50% of such participants eligible
compensation to be paid during the applicable offering period.