According to the CMN (Brazilian Monetary Council) Resolution 2689, since international investors are not established or resident in the country, it is necessary to hire an institution to act as:
Legal Representative: Responsible to present all the registration information of the investor to the Brazilian Authorities. When the representative is an individual or a non-financial corporation, the investor must indicate a financial institution duly authorized by the Central Bank that will be jointly and severally responsible for the representative‘s obligation.
Fiscal Representative: Responsible for taxes and fiscal issues on behalf of the investor before the Brazilian Authorities.
Custodian Responsible: to hold updated reports and control all the assets of the international investor in segregated accounts, and provide this information anytime it is required, to the Authorities and to the investor.
Find more information about how to invest here and ll the information required for the compliance with the market rules for all the trading parties and clearing and custody agents here.