Article 52 of Transitory measures of the Constitution forbids the establishment of branches of foreign financial institutions in Brazil as well as the increase of foreign participation in the capital of Brazilian financial institutions, unless an authorisation is granted resulting from international agreements, reciprocity or expressed interest of the Brazilian Government. For this purpose, financial institutions include banking institutions, credit societies (finance companies), brokerage firms and security dealer companies. 
Since September 2019, the recognition that the envisaged foreign investment would be in line with the Brazilian government’s interest can be made by the Brazilian Central Bank (Decree 10.029/2019). 
On 24 January 2020, the Central Bank of Brazil Circular No.3,977 came into effect. It repeals Circular 3,317 of 29 March 2006 and rescinds the previous authorisation requirements for foreign investment in financial institutions based in Brazil and applies the principle of national treatment of foreign investors to this sector. It implements the Presidential Decree No.10,029 of 26 September 2019, which delegated regulatory power to the Central Bank.


"Article 192. The national financial system, structured to promote the balanced development of the country and to serve the collective interests, in all of the component elements of the system, including credit cooperatives, shall be regulated by supplementary laws which shall also provide for the participation of foreign capital in the institutions that make up the said system.
[...]
[Temporary Constitutional Provisions Act]
 Article 52.  Until such time as the conditions referred to in article 192 are established, the following are forbidden: (CA No. 40, 2002)
I – the installation, in the country, of new branches of financial institutions domiciled abroad;
II – increase of percentual participation of individuals and legal entities resident or domiciled abroad in the capital of financial institutions with headquarters in Brazil.
Sole paragraph. The prohibition referred to in this article does not apply to the authorizations resulting from international agreements, from reciprocity or from interest of the Brazilian Government." (Brazilian Federal Constitution (October 5, 1988), as amended by Constitutional Amendment No. 40 of 2002, Article 192 and Article 52 of the Temporary Constitutional Provisions Act [unofficial translation])
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"Art. 1 The Central Bank of Brazil is authorized to recognize as in the interest of the Brazilian Government:
I - the installation, in the Country, of new branches of financial institutions domiciled abroad; and
II - the increase in the percentage of participation, in the capital of financial institutions headquartered in the country, of individuals or legal entities resident or domiciled abroad. [...]" (Decree No. 10.029 Authorising the Central Bank of Brazil to recognize as in the interest of the Brazilian Government the installation, in the country, of new branches of financial institutions domiciled abroad and the increase in the percentage of participation, in the capital of financial institutions headquartered in the country, of individuals or legal entities resident or domiciled abroad (26 September 2019), Article 1 [google translation])
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"The Board of Directors of the Central Bank of Brazil, in a meeting held on January 22, 2020, based on Decree no. 10,029, of September 26, 2019, and in view of the provisions of article 52, sole paragraph, of the Transitional Constitutional Provisions Act, R E S O L V E S:
Article 1. The Central Bank of Brazil recognizes as of interest to the Brazilian Government the participation, in the capital of financial institutions headquartered in Brazil, by natural or legal persons resident or domiciled abroad.
Sole Paragraph. The participation mentioned in the heading of this article must comply with the requirements and the procedures foreseen in the regulation in effect for establishment, authorization to operate, cancellation of authorization, control changes and corporate reorganizations of financial institutions.
Article 2. The Circular no. 3,317, of March 29, 2006 is hereby revoked.[...]" (Central Bank of Brazil Circular No.3,977 of 24 January 2020)
Brazilian Federal Constitution (October 5, 1988), as amended by Constitutional Amendment No. 40 of 2002, Article 192 and Article 52 of the Temporary Constitutional Provisions Act
Decree No. 10.029 Authorising the Central Bank of Brazil to recognize as in the interest of the Brazilian Government the installation, in the country, of new branches of financial institutions domiciled abroad and the increase in the percentage of participation, in the capital of financial institutions headquartered in the country, of individuals or legal entities resident or domiciled abroad (26 September 2019)
Central Bank of Brazil Circular No.3,977 of 24 January 2020
[<a href="http://www.planalto.gov.br/ccivil_03/Constituicao/Constituicao.htm">Constitution</a>],[<a href="https://www.oas.org/es/sla/ddi/docs/acceso_informacion_base_dc_leyes_pais_b_1_en.pdf">Constitution_Eng</a>],[<a href="http://www.planalto.gov.br/ccivil_03/_ato2019-2022/2019/decreto/D10029.htm">Decree</a>],[<a href="https://www.bcb.gov.br/content/config/Documents/Central_Bank_of_Brazil_BCB_Circular_3977-2020.pdf">Circular</a>]