Mari Sierra focuses her practice on complex cross-border intellectual property litigation, particularly in patent litigation cases. Ms. Sierra has represented some of the world’s leading companies before various courts in Europe, the Courts of England and Wales, Colombia, and the Andean Community and has coordinated litigation strategy in more than 20 countries. Her experience in patent litigation ranges from cancer targeted therapies, molecules, salt forms and antibodies to mechanical products, wireless technology, and FRAND / SEP litigation.

Prior to joining the firm, Ms. Sierra was a paralegal and associate at leading IP litigation boutiques in London and Bogotá respectively. Ms. Sierra is also part of the Leadership Committee of the London Chapter of the ChIPs Network which aims to advance and connect women working in law, policy, STEM and IP.


  • Over the course of her career, Ms. Sierra has represented some of the world’s leading innovative technology companies. Notable experience includes:

    • Coordinating global IP litigation strategies on behalf of a leading life science company in multiple jurisdictions.
    • Acting for a leading life science company resisting the grant of a compulsory license in Colombia over one of its most successful global products.
    • Assisting in obtaining a pan-European injunction on behalf of a leading life science company.
    • Representing a leading US-based pharmaceutical company before the court of the Andean Community with its non-compliance action against a Latin American government for wrongfully granting a compulsory license against one of its most successful products.
    • Acting for plant variety’s owner to obtain a pre-action disclosure order against an alleged infringer in Colombia.
    • Acting for a leading US-based pharmaceutical company in a compliance investigation that involved some of its subsidiaries in Latin America.
    • Representing patent owners and implementers in SEP/FRAND cases, including validity, infringement, essentiality, non-compliance, FRAND rates, licensing negotiations and antitrust issues, including close coordination of parallel proceedings in other jurisdictions.

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  • Education

    • Legal Practice Course, BPP University, 2018

      with commendation
    • LLM, BPP University, 2018

      with commendation
    • Graduate Diploma, Law, BPP University, 2017

      with commendation
    • Postgraduate Diploma, Intellectual Property, Copyright and New Creations, Universidad Externado, 2014

    • LLB, Universidad de la Sabana, 2013

  • Admissions

    • Colombia



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