Decree n. 7.878, of Dec. 27.2012, DOU-I, Dec. 27.2012, provides for the rules to determine the acquisition, sales or maturity date of financial derivatives contracts in Brazil for the purposes of calculating the tax on financial operations (Imposto sobre Operações Financeiras – IOF).
In the cases where, by reason of prior determination of the Central Bank of Brazil, the valid exchange rate for a certain day is defined as the same exchange rate of the immediately preceding day, the acquisition, sales or maturity date will be the date of the immediately preceding business day, and the taxpayer himself will be responsible for consolidating the exchange exposure of those days.
(Decree n. 7.878, 27.12.2012, DOU-I, 27.12.2012. Available at:
<http://www.planalto.gov.br/ccivil_03/_Ato2011-2014/2012/Decree/D7878.htm>. Access in: Jan. 2013).