This excerpt taken from the PNC 10-K filed Mar 2, 2009.
NONQUALIFIED STOCK OPTIONS
Options are granted at exercise prices not less than the market value of common stock on the grant date. Generally, options granted since 1999 become exercisable in installments after the grant date. Options granted prior to 1999 are mainly exercisable 12 months after the grant date. No option may be exercisable after 10 years from its grant date. Payment of the option exercise price may be in cash or shares of common stock at market value on the exercise date. The exercise price may be paid in previously owned shares.