LAWYER PROFILE
Guilherme Valdetaro Mathias

Guilherme Valdetaro Mathias

Brazil 2026

Chambers ranking badge
Chambers ranking badge

Ranked in 3 practice areas

About

Provided by Bermudes Advogados

Brazil: Regions

Career

– Bachelor degree in Law (LL.B.) at Universidade Federal Fluminense (UFF), 1993

– Master (LL.M) in Law at Universidade do Estado do Rio de Janeiro (UERJ), 2000

– Professor of Civil Law (2005 until now) at Escola da Magistratura do Tribunal de Justiça do Estado do Rio de Janeiro (EMERJ)

– Professor of Civil Law (2003 until now) at Fundação Escola Nacional de Seguros (FUNENSEG)

– Professor of Civil Law (2003 until now) of the Specialization Program of Constitutional Civil Law at Universidade do Estado do Rio de Janeiro (UERJ)

– Professor of Civil Law (2002 until now) of the Specialization Program (MBA) of Business Law and Insurance Law at Fundação Getúlio Vargas (FGV/RJ)

– Professor of Civil Law (2000 until now) of the Legal Department at Pontifícia Universidade Católica do Rio de Janeiro (PUC/RJ)

Languages Spoken

Portuguese and French.

Brazil: Industries & Sectors

Practice Areas

In the legal team of the office since 1991, Guilherme Valderato Mathias is currently the Head Partner of the Insurance department and member of the board of Bermudes Advogados. During his career, he performed in dozens of arbitrations and in several legal proceedings in Brazil. Highly skilled in handling insurance, civil, corporate and constructions disputes.

Professional Memberships

– Professor of Civil Law (2005 until now) at Escola da Magistratura do Tribunal de Justiça do Estado do Rio de Janeiro (EMERJ)

– Professor of Civil Law (2003 until now) at Fundação Escola Nacional de Seguros (FUNENSEG)

– Professor of Civil Law (2003 until now) of the Specialization Program of Constitutional Civil Law at Universidade do Estado do Rio de Janeiro (UERJ)

– Professor of Civil Law (2002 until now) of the Specialization Program (MBA) of Business Law and Insurance Law at Fundação Getúlio Vargas (FGV/RJ)

– Professor of Civil Law (2000 until now) of the Legal Department at Pontifícia Universidade Católica do Rio de Janeiro (PUC/RJ)

Brazil: Contentious

Practice Areas

Dispute Resolution: Civil law, contracts, regulatory law, tort, civil litigation, and arbitration.

Career

Litigation partner specialized in complex disputes involving real estate, insurance, corporate, commercial, and finance contracts, Guilherme is recognized as a leading litigator and recommended as an “efficient and hard-working lawyer” by Chambers.

Professional Memberships

Brazilian Bar Association (OAB/RJ, OAB/SP, OAB/DF).

Publications

Author of articles and chapter of books on dispute resolution matters published by Revista de Arbitragem e Mediação, Revista dos Tribunais, Revista do Direito da Energia, among others.

Personal

Partner at Sergio Bermudes Advogados since 1994.

Professor of Civil Law at PUC-Rio, FGV-Rio, Magistracy School of the Rio de Janeiro State Court of Justice (EMERJ), Fundação Escola Nacional de Seguros (FUNENSEG), State University of Rio de Janeiro (UERJ), and at the MBA Program in Business Law and MBA Program in Insurance Law at Fundação Getúlio Vargas (FGV-Rio).

LL.M in Civil Law from UERJ.

LL.B from Fluminense Federal University (UFF).

Chambers Review

Provided by Chambers

Chambers Brazil: Contentious

Dispute Resolution: Litigation: The Elite - Brazil

Band 4
Band 4

Individual Editorial

Guilherme Valdetaro Mathias dedicates his practice to litigation mandates, representing clients in corporate disputes, annulment of litigation settlements and contractual disputes.

Chambers Brazil: Industries & Sectors

Insurance - Brazil

Band 3
Band 3

Individual Editorial

Guilherme Valdetaro Mathias is a noteworthy lawyer with a history of working in strategic litigation matters before the Higher Courts. His knowledge and client service have been commended by the companies that work with him, especially those from the health insurance field.

Chambers Brazil: Regions

Dispute Resolution: Rio de Janeiro - Brazil

Band 3
Band 3

Individual Editorial
Partner Guilherme Valdetaro Mathias is an experienced litigator strongly involved in disputes in Rio de Janeiro. He is best known for representing high-level clients in sophisticated corporate disputes.

Strengths

Provided by Chambers

  • Guilherme Valdetaro has an impressive litigation knowledge and is always available.

    Dispute Resolution: Litigation: The EliteChambers Brazil: Contentious
  • Guilherme Valdetaro is well known in the litigation market.

    Dispute Resolution: Litigation: The EliteChambers Brazil: Contentious
  • Guilherme Valdetaro Mathias distinguishes himself from any other insurance lawyer through his exceptionally high capacity for procedural assessment, as well as his effective and innovative solutions. Plus, his risk assessment skills are unparalleled.

    InsuranceChambers Brazil: Industries & Sectors
  • When I close my eyes and think of an insurance lawyer, Guilherme Valdetaro's image is the one that comes to my mind. Calm, accessible and highly communicative, he's someone whose knowledge really reassures us.

    InsuranceChambers Brazil: Industries & Sectors
  • A notable figure in the insurance and reinsurance markets, Guilherme Valdetaro is a lawyer who effectively defines strategies and always strives to provide the most satisfactory service to his clients. He has an outstanding track record in the Superior Courts.

    InsuranceChambers Brazil: Industries & Sectors
  • Guilherme Valdetaro Mathias shows technical precision and attention in developing strategies of defence. His experience as a professor of civil law is very helpful in shaping arguments.

    Dispute Resolution: Rio de JaneiroChambers Brazil: Regions

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Brazil

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