This excerpt taken from the PBR 20-F filed May 22, 2009.
Taxation of Capital Gains
Upon the sale or other disposition of a share or an ADS, a U.S. holder will generally recognize gain or loss for U.S. federal income tax purposes. The amount of the gain or loss will be equal to the difference between the amount realized in consideration for the disposition of the share or the ADS and the U.S. holders tax basis in the share or the ADS. Such gain or loss generally will be subject to U.S. federal income tax and will be treated as capital gain or loss. The net amount of long-term capital gain recognized by an individual holder before January 1, 2011 generally is subject to taxation at a maximum rate of 15%. Capital losses may be deducted from taxable income, subject to certain limitations.
A non-U.S. holder will not be subject to U.S. federal income tax or withholding tax on gain realized on the sale or other disposition of a share or an ADS unless: