Gemma Barrett

Gemma Barrett


Gemma is an experienced and trusted advisor for some of the world’s leading life sciences and chemical companies. 

She has more than ten years’ experience advising clients in patent litigation matters before the English Courts and providing strategic advice in relation to complex, multi-jurisdictional patent portfolios. Her advice is technically excellent but also takes into account wider commercial implications.

Gemma's stellar academic background in biochemistry underscores her proficiency in navigating disputes spanning small molecule pharmaceuticals, molecular diagnostics, biologics, antibodies, antibody technology and industrial chemical processes. Her litigation expertise includes securing preliminary injunctions, advising on global cross-border litigation, and coordinating worldwide litigation, working closely with multi-disciplinary teams in the defence and enforcement of patent portfolios. Gemma has developed innovative and successful strategies, often combining patent and regulatory law, to assist pharmaceutical companies in the enforcement of their rights.

Gemma has a wealth of experience in domestic and international arbitrations, particularly in technical domains, managing numerous cases with substantial damages claims. Beyond her legal practice, she actively contributes to industry knowledge through publications, including co-authoring chapters and providing insights into UK and EPO case law for various IP publications.


Representative matters

A high profile patent revocation action at High Court and Court of Appeal relating to the anticoagulant apixaban (previous firm experience).

Patent revocation action relating to a biologic product for the treatment of multiple sclerosis (previous firm experience).

Patent litigation for a large pharmaceutical company at High Court and Court of Appeal proceedings relating to their small molecule product for the treatment of eye disorders (previous firm experience).

Coordination of multi-jurisdictional patent disputes for large pharmaceutical companies (previous firm experience).

Gemma Barrett, whom clients describe as "a brilliant and highly passionate patent litigator with an in-depth understanding of the complex legal and technical details of her cases. She is very efficient and responsive and always provides excellent strategic and legal advice, often within very tight timelines".
IAM Patent 1000
Competitors describe Barrett as "easy going and friendly; she is a strategist, who makes strong arguments".
JUVE One to Watch 2023


  • Legal 500 Next Generation Partner 2024
  • JUVE Rising Star 2023



Admitted as a Solicitor in England and Wales


MBiochem, Molecular and Cellular Biochemistry, University of Oxford, 2004

Diploma in Intellectual Property Law and Practice, University of Oxford, 2010

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A&O Shearman was formed on May 1, 2024 by the combination of Shearman & Sterling LLP and Allen & Overy LLP and their respective affiliates (the legacy firms). Any matters referred to above may include matters undertaken by one or more of the legacy firms rather than A&O Shearman.