Jacquelyn MacLennan | White & Case LLP International Law Firm, Global Law Practice
Jacquelyn MacLennan
Jacquelyn MacLennan

Jacquelyn MacLennan

Partner, Brussels, London

“A superb practitioner and very good public speaker who always looks for solutions.”

Chambers Europe 2015


Jacquelyn MacLennan offers a wealth of experience for clients worldwide, representing leading multinational corporations, governments and trade associations.

She focuses on EU competition law, and clients benefit from her experience and insight in developing strategy and running major international cartel investigations, as well as advising on complex distribution problems and licensing arrangements, abuse of dominance cases, mergers and joint ventures.

Jacquelyn is a core team member of the firm's Business & Human Rights Interest Group and advises on issues related to corporate supply chain compliance, disclosure requirements, and Business & Human Rights issues generally.

She also advises on EU customs and trade law, international sanctions, and EU regulatory requirements, notably in respect to product safety and environmental regulation.   

With an impressive track record of experience and know-how, Jacquelyn litigates regularly before the EU and UK courts, and represents clients before the European Commission.

Jacquelyn has accumulated substantial management experience over her career; she is currently a member of the Partnership Committee (the main governance body) of White & Case, and a former Member of the Executive Committee (responsible for the firm's strategy) and Executive Partner heading the Brussels office. In October 2015, she became the Global Pro Bono Practice Leader.

Clients describe Jacquelyn as "excellent – an industry leader in antitrust matters" and "commercially-minded and solution-oriented." (Chambers Europe, 2016)

Bars and Courts

  • Solicitor in Scotland
  • Notary Public
  • Brussels Bar


  • Diploma in Legal Practice, University of Edinburgh
  • LLB (Hons), University of Edinburgh


  • English
  • French


Toshiba—global proceedings—appeal to Court of Justice of the EU and current appeal to General Court

Jacquelyn is representing Toshiba Corporation in multijurisdictional proceedings concerning Gas Insulated Switchgear. This involved a successful appeal of the original European Commission decision fining Toshiba €90.9 million for participating in a global cartel to the European General Court—where the Court annulled in full the fine on Toshiba—and a further appeal to the Court of Justice of the EU. An appeal to the General Court is now pending of the new, lower, fine imposed by the Commission.

Major multinational—customs issue

Jacquelyn represented a major multinational in successful proceedings involving the World Customs Organization, European Commission, national customs authorities and national courts concerning the classification of insulated-gate bipolar transistors.

Toshiba—preliminary ruling to Court of Justice of the EU

Jacquelyn represented Toshiba in a seminal preliminary ruling to the European Court of Justice, which established the principles governing the scope for parallel proceedings by national competition authorities and the European Commission.

US chemicals multinational—customs matters

Jacquelyn advises a US chemicals multinational on a range of high-level customs matters, including rules of origin, tariff quotas and special customs procedures (such as temporary importation).

Toshiba—appeal to European General Court

Jacquelyn is representing Toshiba in an appeal to the Court of Justice of the EU of the Commission Decision in Cathode Ray Tubes (CRT) used for TVs and computer monitors, regarding the conduct of a JV for which it was held liable, having successfully had liability and a fine of €28 million quashed by the European General Court.

Multinational corporations—environmental issues etc.

Jacquelyn is advising major multinational corporations on environmental issues at EU and at national level, as well as handling compliance issues, including inspections by competent authorities, and product recalls.

Toshiba—appeal to Court of Justice of the EU

Jacquelyn represented Toshiba in an appeal to the Court of Justice of the EU against a Commission Decision finding a home market protection agreement in Power Transformers.

Speaking Engagements

Speaker, Brexit Roundtable, 24 June 2017: 56th London-Leiden Meeting,

Workshop Leader, "The Role of Law", 19-20 June 2017: FT-RSG Innovative Lawyers Summit,

Moderator, 2nd annual plenary, 24 April 2017: European Justice Stakeholders Forum (EJSF),

"Jessup's Legacy: Practical Action and New Ideas – The Role of Business in Human Rights", 15 April 2017: Keynote address, Jessup International Moot Court Competition 2017, Championship Round,
Washington, DC

"Continental Divide: Differing Approaches to Loyalty Incentives: Rebates as an Abuse of Dominance in the EU and US", 29 March 2017: ABA Antitrust Law Spring Meeting,
Washington, DC

Judge, Jessup International Moot Court Competition 2017, 18 February 2017: Belgian National Rounds,

"Fighting Forced Labour in the Supply Chain", 17-19 January 2017: World Economic Forum,

Panel Moderator, "One Decade, One Project: Ten Years of Pro Bono to Prevent Genocide and Mass Atrocity Crimes", 16 November 2016: PILnet 10th Annual European Pro Bono Forum,

"What Does It Mean for Law?", October 6, 2016: The Conference Board unConference on "The Future of Digital Transformation and Innovation",

"Breaking Gender Unconscious Bias: How to Gain a Level Playing Field", October 5, 2016: C5 Women in Compliance Conference,


Awards & Recognition

Top Ten Innovative Lawyers in Europe – FT Innovative Lawyers 2018

Best in Competition & Antitrust, Euromoney Women in Business Awards – Europe, 2016 and 2017

Who's Who Legal: Competition, 2017

Leading Lawyer: Competition/European Law — Belgium, Chambers Europe 2017

Leading Lawyer: Environment: EU Regulatory — Belgium, Chambers Europe 2016

Leading Lawyer: International Trade/WTO — Europe-wide, Chambers Europe 2015

Leading Lawyer: International Trade/WTO — Belgium, Chambers Europe 2015

Recommended: Not-for-profit – Belgium, Legal 500 EMEA 2018

Recommended: Competition: EU and global – Belgium, Legal 500 EMEA 2017

Honorary Fellow, Europa Institute, University of Edinburgh

Best Business Anticompetitive Practices Article, 2012 Antitrust Writing Awards

Member of Chatham House

Member of the Environmental Law Network International (elni)

Member of IBA Pro Bono Committee and Human Rights Law Committee

Member of PILnet's Pro Bono Leadership Committee