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Portrait of Ruth Derruau

Ruth Derruau

Senior Associate

CMS Cameron McKenna Nabarro Olswang LLP
Cannon Place
78 Cannon Street
United Kingdom
Languages English, French

Ruth is a Senior Associate in the Competition & Trade Team in London. She has advised on a range of antitrust, merger control, regulatory and procurement matters for over seven years. Ruth advises clients across a number of industry sectors with a particular focus on the energy and consumer products sectors.

Ruth has both UK and EU merger control experience, having obtained clearances for clients in Phase 1 and Phase 2 proceedings, both unconditionally and with remedies. She advises several international companies on competition issues in their distribution and pricing arrangements. Ruth also advises on state aid, procurement and consumer protection law.

Ruth graduated in Law with French and studied at both Cardiff University and Université de Toulouse 1. She joined CMS Cameron McKenna in March 2014.

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Relevant experience

  • A global consumer goods company on its distribution/pricing policy.
  • Major international companies on competition law “behavioural” issues including abuse of dominance and restrictive practices.
  • Trade associations on competition issues relating to the conduct of their meetings as well as their constitution and governance arrangements.
  • Various clients on competition law compliance and dawn raids.
  • Companies in a range of sectors on merger clearances at UK, EU and multi-jurisdictional levels.
  • Various companies in the energy sector, on the state aid implications of renewable and other projects.
  • Post Office Ltd on the design and implementation of its tower procurements and other procurements.
  • National Grid on procurement matters relating to various projects.
  • Suppliers active in a variety of sectors on potential procurement challenges.
  • Microsoft on the CMA’s consumer law investigation into the supply of online gaming memberships.
  • A secondary ticketing platform on the CMA’s consumer law investigation into the online secondary tickets market.
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Memberships & Roles

  • Law Society's Competition Section
  • Competition Law Association
  • Procurement Lawyers’ Association
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  • 2015 – Postgraduate Diploma in EU Competition Law, King’s College, London
  • 2009 – Postgraduate Diploma in Legal Practice, The College of Law, Guildford
  • 2008 – LL.B in Law and French, Cardiff University, Cardiff 
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Get in contact with


21 October 2019
The UK Gov­ern­ment puts for­eign in­vest­ment con­trol firmly back on the agenda
On 14 Oc­to­ber 2019, the UK Gov­ern­ment an­nounced plans to in­tro­duce new le­gis­la­tion to strengthen the Gov­ern­ment’s ex­ist­ing powers to scru­tin­ise and in­ter­vene in busi­ness trans­ac­tions on the grounds...
04 July 2019
CMA an­nounces mar­ket study in­to on­line plat­forms and di­git­al ad­vert­ising 
On 3 Ju­ly 2019, the CMA launched a mar­ket study in­to on­line plat­forms and di­git­al ad­vert­ising. This fol­lows re­peated calls from vari­ous com­mit­tees and re­views for the CMA to scru­tin­ise the sec­tor, giv­en...