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Guillermina Ester

Guillermina Ester

Global 2026

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Pérez-Llorca
 Pérez-Llorca

Ranked in 1 practice area

Litigation: Elite

Spain

2 years ranked

About

Provided by Pérez-Llorca

Global

Practice Areas

Arbitration and Litigation. Guillermina Ester focuses her practice on civil, commercial and corporate litigation and arbitration involving unfair competition, shareholder disputes and directors’ liability, contractual disputes, construction disputes, banking litigation and civil liability. Experience advising international and start-up companies who value her thoroughness and hands-on approach.

Career

Joined Pérez-Llorca in 2005 and made partner in 2010. 5 years’ experience at previous firm. Law degree (Universidad Carlos III, Madrid, 1999). General Management Programme (PDG) (IESE Business School, 2018). Languages: Spanish and English

Professional Memberships

Madrid Bar Association, Spanish Arbitration Club (CEA)

Chambers Review

Provided by Chambers

Chambers Global Guide

Litigation: Elite - Spain

Band 2
Individual Editorial

Guillermina Ester regularly advises clients on contractual, competition and shareholder disputes. She also handles disputes at the ECJ.

Learn more about this teamView ranking table

Strengths

Provided by Chambers

  • Guillermina is reliable and a strong contributor to the team’s overall performance.

    Litigation: EliteChambers Global Guide

  • She offers great solidity, capacity for effort and attention to detail.

    Litigation: EliteChambers Global Guide

  • Guillermina has a spectacular strategic outlook, knowing how to combine technical knowledge with complex situations.

    Litigation: EliteChambers Global Guide

  • Guillermina is an excellent professional with technical preparation and a great customer orientation. She provides a clear view of business and legal risks and recommends the best alternatives.

    Litigation: EliteChambers Global Guide

Ranked Individuals at Pérez-Llorca (76)

Colombia

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