Sandra Duerden

Overview

I'm a Partner and an Advocate in our Guernsey Litigation practice, with over 15 years' experience at Mourant.

I specialise in commercial litigation and contentious trusts disputes. I have a particular interest in commercial or trust disputes involving private international law aspects and cross-border disputes (particularly those which raise issues of jurisdiction and enforcement of foreign judgments). I also advise on insolvency and regulatory/compliance matters.

In addition to my contentious work, I have a strong expertise in intellectual property law and am recognised as one of the few Guernsey intellectual property law specialists. I’ve advised clients in infringement disputes involving trademarks and copyrights, and regularly provide practical guidance for individuals and companies on aspects of Guernsey intellectual property laws.

I'm fluent in English and French, and I have a good knowledge of German and Lingala.

Professional qualifications

• Advocate, Guernsey, 2011
• Solicitor, England and Wales, 2010 (currently non-practising)
• Legal Professional Course, 2010
• Graduate Diploma in Law, 2008
• Master in Commercial Law with Northumbria University, 2006
• Master in Political Sciences as an Erasmus student at Warwick University, 2004
• French Licence in Law at the University of Lille (France), 2003
• French and German Law DEUG at the University of Saarland (Germany), 2002

Work highlights

• Acting for a corporate trustee in a contested Public Trustee v Cooper application regarding the decision to divide a multi-million dollar trust fund between two sides of a family
• Advising on challenges to the validity of Guernsey trusts against allegations of sham in foreign forced heirship claims
• Acting in estates' disputes and applications for the removal of trustees or personal representatives
• Acted for a professional executor in defending costs claims arising out of hostile proceedings by the beneficiaries, which included a claim for repayment of the executor's fees to the estate
• Successfully defended an emergency injunction sought on one hour notice by beneficiaries to stop the trustee of an EBT exercising its voting rights at the employer's AGM that morning
• Running local and cross-border recovery and enforcement actions, including acting for regulated lenders in saisie proceedings and enforcing foreign judgments against Guernsey assets
• Representing liquidators and administrators in court procedures, including compulsory liquidation application, directions application, discharge of orders

Memberships

• The Guernsey International Legal Association
• INSOL International
• The Guernsey IP Commercial Group
• Guernsey Registered Image Rights Agent, Patent Agent and Trade Mark Agent

What the directories say

In Legal 500 UK 2025, Sandra is named as a Recommended Lawyer in both Dispute Resolution and Private Client, Trusts and Tax. She is described as an "exceptional lawyer."

In Legal 500 UK 2024, Sandra is named as a Recommended Lawyer in Dispute Resolution and Private Client, Trusts and Tax. A source in the guide describes her as "exceptional", praising her "experience, strong communication skills and responsiveness."

In Legal 500 UK 2023, Sandra is a Recommended Lawyer for Dispute Resolution and specifically for her contentious trusts practice.