This excerpt taken from the NKE 10-K filed Jul 27, 2009.
Responsibility for Taxes. The following provision supplements Section 4 of the Agreement:
By accepting the Option, the Optionee agrees that, immediately upon exercise of the Option, he or she will notify the Employer of the amount of any gain realized. If the Optionee fails to advise the Employer of the gain realized upon exercise, he or she may be liable for a fine. The Optionee will be solely responsible for paying any difference between the actual tax liability and the amount withheld.
Tax Clearance Certificate for Cash Exercises. If the Optionee exercises the Option using a cash exercise method, the Optionee must obtain and provide to the Employer, or any third party designated by the Employer or the Company, a Tax Clearance Certificate (with respect to Foreign Investments) bearing the official stamp and signature of the Exchange Control Department of the South African Revenue Service (SARS). The Optionee must renew this Tax Clearance Certificate every twelve months, or such other period as may be required by the SARS. If the Optionee exercises by a cashless exercise method whereby no funds are remitted out of South Africa, no Tax Clearance Certificate is required.
Exchange Control Information. The Optionee should consult his or her personal advisor to ensure compliance with applicable exchange control regulations in South Africa; as such regulations are subject to frequent change. The Optionee is responsible for ensuring compliance with all exchange control laws in South Africa.