UK Guide 2026 : London (Firms)
Ranked Individuals
Provided by Simmons & Simmons LLP
Our competition team have represented defendants in some of the largest and most high profile investigations conducted by competition authorities in Europe. We have hands on experience of international cartel investigations and cutting edge abuse of dominance cases as well as in depth merger investigations. We further advise on the application of EU State aid rules and assist clients on the Brussels notification and investigation process. We also have broad regulatory experience, advising government and regulatory bodies, private sector investors and operators across a range of regulated sectors (notably financial institutions, transport, water, energy, Life Sciences and TMT). We represent clients before the Court of Justice of the European Union, the European Commission, national courts and enforcement agencies.
Through our network of international offices, clients come to us for advice on the complete range of services in:
Our EU, Competition and regulatory teams are located in Brussels, close to the main EU institutions, and in the main EU jurisdictions (France, Germany and the UK).
Provided by Chambers
Simmons & Simmons has experience in both contentious and non-contentious competition law matters. The law firm represents clients in damages claims, class actions and complaints of anti-competitive behaviour. The team often assists clients with the notification of mergers to the CMA.
Provided by Chambers
Simmons & Simmons defended Google in a proposed opt-out collective proceeding at the CAT concerning alleged abusive conduct.
Provided by Chambers
The lawyers were very responsive and provided hugely valuable input into the case strategy.
Simmons & Simmons is strategically very sound and extremely commercial. The team is a pleasure to work with.
Simmons & Simmons is distinguished by its practical approach, wide territorial coverage and great team.
The lawyers work really closely with their clients, becoming an extension of the in-house team.
The team worked extremely hard to get on top of all of the documentary material, factual and expert evidence in a very big case.
Provided by Chambers
Patrick Boylan is highly experienced in advising clients on high-stakes competition litigation and collective proceedings. He is notably sought after by clients in the life sciences and TMT sectors. He has experience representing both claimants and defendants.
He is an excellent black letter lawyer.
Patrick Boylan is an expert in his field and a trusted partner.
Patrick Boylan is realistic, pragmatic and commercial. He can stand back and see the realities and overview of the situation.
Sarah Smith often acts for clients on CMA merger clearance investigations. She offers additional experience in appeals against regulatory decisions, frequently on behalf of clients in the pharmaceutical sector. She joined Simmons & Simmons in January 2025.
Sarah Smith is very switched on, has a lovely manner with clients and knows her stuff.
I rate her highly.
Eleanore Di Claudio enters the rankings this year on the back of notable work representing clients from the TMT sector in high-profile competition litigation cases.
Eleanore Di Claudio is ridiculously clever.
I think she has an impressive eye for detail and has a real persistence in making points.
Competition Law
Competition Law: Litigation
Competition Law: Litigation
Provided by Simmons & Simmons LLP
Sarah Smith
View profile of Sarah SmithEleanore Di Claudio
View profile of Eleanore Di ClaudioPatrick Boylan
View profile of Patrick Boylan
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