About
Mark is a market-leading defence-side competition litigator. He has unsurpassed experience of litigating antitrust damages claims and collective proceedings, having handled many of the leading cases, and has an unmatched record of success – see the experience list below for some recent highlights.
Working as part of the top-ranked antitrust litigation team at Freshfields, Mark uses his leading experience and tactical acumen to maximise outcomes for clients, as his track record of success attests.
Mark continues to practise fully alongside serving in a management role as Freshfields’ firmwide Client Partner, overseeing the firm’s global client strategy. In his client work, he brings a hands-on approach that clients value, delivering forward-thinking strategies that minimise exposure and help clients, including boards and senior stakeholders, understand and manage financial and reputational risk.
With unmatched experience in defending clients from damages actions before the UK courts and Competition Appeal Tribunal (CAT), Mark has played a pivotal role in many of the leading UK competition damages cases. He is particularly known for his work defending opt-out collective proceedings in the CAT, having acted on the defence side of many of the defining cases.
Mark is a member of the CAT User Group, which advises the CAT on the development of its rules and procedures. In addition, he has previously held roles on the ABA's Antitrust Global Private Enforcement Committee, and has a deep...
- Defending Mastercard in the leading Merricks v Mastercard collective proceedings before the UK’s CAT, Court of Appeal and Supreme Court, including in relation to the collective settlement of the proceedings and subsequent challenges to the settlement. Reportedly the largest damages claim ever brought in the UK, the claim was pivotal in shaping the approach to all UK antitrust class actions.
- Mark is also defending Mastercard in multiple separate collective proceedings in the CAT and in the Merchant Umbrella Proceedings.
- Successfully represened London and South Eastern Railway in the Gutmann v LSER collective proceedings concerning rail tickets, the first standalone and first alleged abuse of dominance related collective proceedings brought in the CAT under the UK's competition class action regime. The claim was fully defended on liability and is a leading authority on the intersection between abuse of dominance and consumer protection.
- Also acted successfully for Govia Thameslink Railway in the Gutmann v GTR and Boyle v GTR opt-out collective proceedings, also standalone abuse claims concerning rail tickets, and on which GTR prevailed.
- Acting for ABB in the leading BritNed v ABB High Court action and in the Court of Appeal. The case was the first cartel damages follow-on claim to go to final judgment at first instance, and on appeal, in the UK. ABB defended the claim successfully at trial and prevailed on all points in the Court of Appeal.
- Successfully defending Infineon Technologies in the UK High Court and Court of Appeal in the Gemalto v Infineon & Ors High Court follow-on damages claim arising out of the European Commission's infringement decision in relation to smartcard chips. The case is now a leading authority on limitation.
- Defending BT/EE in the Gutmann collective proceedings regarding alleged “loyalty penalties” charged by UK Mobile Network Operators to customers of combined handset and airtime agreements beyond the end of their minimum contractual term.
- Acting for Welcome Break in relation to proposed abuse of dominance collective proceedings concerning Motorway Service Area fuel prices.
Mark Sansom
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