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Siobhan Kahmann

Of Counsel

CMS EU Law Office
Avenue des Nerviens 85
1040 Brussels
Languages English, French

Siobhan has practised EU and UK competition law for over ten years in Brussels and the UK, in addition to counselling clients on regulatory, policy and trade matters. Her competition experience has included: comprehensive competition law compliance programmes and training; complex cartel infringement assessments, defence, and leniency applications; detailed vertical, horizontal, tech transfer and motor vehicle agreement analysis and support; substantial advice following the Commission’s e-commerce inquiry; strategic and in-depth counsel for clients in abuse of dominance claims as defendant, complainant and victim; and significant experience in matters on UK, European and international merger control. 

She has extensive experience advising on competition law in the tech industry, including big data and artificial intelligence, in addition to automotive and other transport, and on FMCG issues. Siobhan has also recently spent over a year working as an in-house competition counsel at a global oil and gas company, where her focus included advising on new energies initiatives and electric car charging infrastructure. She also specialises in different aspects of tech regulation, including net neutrality, and autotech.

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Relevant experience

  • Cartel defence: advising clients across different industries on cartel defence strategies and procedures in the EU and at national level including leniency applications, and all stages of investigations. 
  • E-commerce: engaging in comprehensive e-commerce review, training and strategy for clients in a number of different sectors and jurisdictions.
  • Agreements: providing detailed and practical legal advice and training to a diverse range of MNCs on vertical, horizontal and other complex arrangements.
  • Abuse of dominance: counselling clients on formulating abuse of dominance complaints including strategy and policy towards regulators and responses to investigations, in addition to defence approaches and official responses.
  • Compliance programmes: compiling extensive and tailored compliance programmes and training for various clients across numerous sectors and jurisdictions, including designing e-learning modules.
  • Merger control: strategically advising on and securing the clearance of a number of mergers, including but not limited to the automotive industry, at both national and European level.

Other Regulatory

  • Net Neutrality: advising on pan-European net-neutrality issues, with a focus on zero-rating.
  • AV: counselling clients in the evolving electric/autonomous vehicle and energy industry on a range of regulatory issues and policy support.
  • Regulatory: providing legal support and analysis across a wide-range of EU regulatory issues including energy, emissions, CRS, free movement and environmental frameworks.
  • Trade: preparing trade submissions for a variety of different EU and WTO procedures.
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  • LL.B Honours, University of Aberdeen
  • LL.M, EU Competition and Business Law, Universiteit van Amsterdam
  • DLP, University of Edinburgh 
  • QLTT English Law, College of Law
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  • Solicitor and Notary Public, Law Society of Scotland
  • Solicitor, Law Society of England and Wales
  • Solicitor, Ireland
  • Avocaat Brussels Bar A-List (Flemish)
  • Writer of the Signet to her Majesty the Queen (WS)
  • Council Member (International), Law Society of Scotland
  • Committee Member, Competition, Tech Law, and International Trade Committees, with the Law Society of Scotland
  • Observer Member in the EU Law Committee, Member of the Competition Section, Law Society of England and Wales
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Siobhan is a regular contributor and presenter on a range of legal developments including competition law, e-commerce, big data, net neutrality, technology law, and electric and autonomous vehicles. She has also written and presented extensively on Brexit, including on competition law, and lawyers’ practising rights.

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