Sarina Williams

Dispute Resolution Partner, London

"I advise on a wide range of contentious and regulatory matters, with a particular focus on complex, high-value competition litigation before the English courts, and the conduct of regulatory investigations and enforcement. I aim to provide clear and commercial advice to help clients develop strategies to resolve complex disputes."


Education and qualifications


Sarina is a Partner in the Dispute Resolution team. She has wide-ranging experience advising corporates and financial institutions on contentious and regulatory matters, particularly in relation to competition litigation and financial and competition regulatory issues.

Sarina has extensive experience in the conduct of complex, high-value competition litigation before the High Court of England and Wales. She is currently acting for defendants in a large number of high-value proceedings (involving claims in excess of £1 billion) related to the alleged antitrust infringements concerning interchange fees, which were subject to a ten day hearing before the Court of Appeal in 2018 and a four day hearing before the Supreme Court in January 2020.

She is also advising a defendant in relation to Part 20 contribution proceedings relating to the power cables cartel and several clients in connection with competition investigations in the pharmaceutical sector.

On the contentious regulatory side, Sarina has extensive experience advising major banks and financial institutions on FCA enforcement investigations, including in relation to complaints handling, transaction reporting, conducting internal investigations, and whistleblowing.

Sarina works in close collaboration with lawyers from the firm’s other market-leading practice areas, including Competition, Financial Regulation and Corporate in cross-office, multidisciplinary teams.

Sarina is passionate about social mobility, gender equality, and ending the stigma around mental health awareness.

Work highlights

Sarina’s recent matters include:

  • acting for a leading payment scheme in relation to numerous “stand alone” litigation proceedings brought by major retailers alleging that multilateral interchange fees on card transactions were levied in breach of Article 101 TFEU (and various domestic competition laws);
  • acting for a defendant regarding Part 20 contribution proceedings brought in the UK in relation to damages actions following from the power cables cartel;
  • advising a number of clients in relation to competition law investigations by the European Commission and the Competition and Markets Authority;
  • advising an interested party on a judicial review of a FOS decision relating to PPI;
  • advising a large insurer on the FCA’s market study on competition in the wholesale insurance broker market;
  • advising a major bank on an FCA investigation into its transaction reporting; and
  • advising a major bank on an FCA investigation into its internal investigations policies.

Education and qualifications

Sarina studied Law at Downing College, University of Cambridge.