Mrs Anna Cecilia Rostworowski da Costa Buff > Castro Barros Advogados > Sao Paulo, Brazil > Lawyer Profile

Castro Barros Advogados
SÃO PAULO, SP, CEP 04552-000

Work Department

Corporate and M&A
Business Contracts
Capital Market


Practice focused on M&A, including as head of due diligence procedures, in the draw-up and negotiation of SPAs and asset purchase agreements, shareholders’ agreements and others. Anna Cecilia advises foreign clients in asset purchases in Brazil, including with respect to foreign investments, draw-up of business contracts and organization of structured transactions. Anna Cecilia has also been part of the Public Law team of law firm Baker & McKenzie, in Paris, having advised both government agencies and private companies. Anna Cecilia has been listed as one of the leading Capital Market and M&A by Legal 500 and Chambers Latin America, and as Foreign Expert for France by Chambers, in 2018.


Partner with Castro Barros Advogados since 2012


Portuguese, English, French.


International Bar Association, IBA (2018)
Brazilian Bar Association

– Rio de Janeiro Chapter (2011)
– São Paulo Chapter (2002)


Master’s degree in Public Economic Law – Université Paris II – Pantheón-Assas (2007-2008)

Administrative Law Course – Brazilian Public Law Society -SBDP (2004)
Bachelor of Laws – Mackenzie Presbyterian University (2002)

Lawyer Rankings

Brazil > Corporate and M&A

Castro Barros Advogados‘ corporate team operates from the firm’s Rio de Janeiro and São Paulo offices; in M&A, the team commonly represents buyers, though it has also grown its seller-side caseload. Anna Cecilia Rostworowski da Costa Buff‘s practice spans corporate, competition and regulation; Helen Gaudio Valente advises on M&A, project finance and contracts; and Fernanda Alves Wolf has knowledge of corporate, contracts, judicial recovery and capital markets law.