Esso Petroleum Co Ltd v Mardon [1976]

Esso Petroleum Co Ltd v Mardon [1976] EWCA Civ 4 is a notable English contract law case concerning misrepresentation. The Court of Appeal held that the divide between a statement of opinion and fact becomes more factual if one holds himself out as having expert knowledge.

Mr Mardon was purchasing a petrol station franchised by Esso Petroleum Co Ltd. Esso provided an estimate that the throughput of a petrol station in Southport would be 200,000 gallons a year. However, this estimate did not take into account a local council decision that affected the accessibility of the station, leading to fewer customers. Mr Mardon relied on this estimate when purchasing the petrol station, and business did not go as expected.

Lord Denning MR, in the Court of Appeal, held that there was a contractual warranty, and damages were not limited. He considered Esso's estimate to be a forecast made by a party with special knowledge and skill. Even though it may not have been a guarantee, Lord Denning interpreted it as a warranty that the forecast was sound and reliable, made with reasonable care and skill. He explained that if a person with special knowledge makes a forecast, intending the other party to act upon it, and they do act upon it, it can be seen as a warranty.

Lord Denning distinguished the case from Bisset v Wilkinson [1927], stating that in Esso v Mardon, Esso had special knowledge that Mr Mardon did not possess. The damages awarded were for the loss suffered, not the loss of a bargain. Lord Denning also argued that even without a warranty, there would still be negligent misrepresentation liability in tort. He rejected the notion that when a contract results, there is no tort liability, emphasising the duty to negotiate with care when a party with special knowledge makes a representation with the intention of inducing another to enter into a contract.

In summary, the case established that a statement of opinion can be treated as a warranty if made by a party with special knowledge and skill, and damages for negligent misstatement can be awarded in both contract and tort.
Back to blog

UOL Case Bank

Upon joining, you become a valuable UOL student and gain instant access to over 2,100 case summaries. UOL Case Bank is constantly expanding. Speed up your revision with us now.

Subscribe Now

Where are our students from?

Yale University
Council of Europe
Baker Mckenzie 
University of Chicago
Columbia University
New York University
University of Michigan 
University College London (UCL)
London School of Economics (LSE)
King’s College London (KCL)
University of London
University of Manchester
University of Zurich
University of York
Brandeis University
University of Exeter
University of Sheffield
Boston University
University of Washington
University of Leeds
University of Law
Royal Holloway, University of London 
Birkbeck, University of London
SOAS, University of London
University of Kent
University of Hull
Queen’s University Belfast
Toronto Metropolitan University
Hong Kong University of Science and Technology
University of Buckingham

  • Criminal Practice

    Diagrams and Charts

    Our carefully designed diagrams and charts will guide you through complex legal issues.

  • Criminal Law

    Clear and Succinct Definitions

    Key concepts are concisely defined to help you understand legal topics quickly.

  • Property Law

    Statutory Provisions

    Statutory provisions are provided side by side with legal concepts to help you swiftly locate the relevant legislation.

  • Public Law

    Case Summaries

    We have summarised important cases for you so that you don't need to read long and boring cases.

  • Evidence

    Rules and Exceptions

    Rules and exceptions are clearly listed so that you know when a rule applies and when it doesn't.

  • Company Law


    Legal terms and key concepts are explained at the beginning of each chapter to help you learn efficiently.

  • Case Law

    Case law is provided side by side with legal concepts so that you know how legal principles and precedents were established.

  • Law Exam Guide

    Law Essay Guide

    You will learn essential law exam skills and essay writing techniques that are not taught in class.

  • Law Exam Guide

    Problem Question Guide

    We will show you how to answer problem questions step by step to achieve first-class results.

  • Conflict of Laws

    Structured Explanations

    Complex legal concepts are broken down into concise and digestible bullet point explanations.

  • Legal System and Method

    Legal Research

    You will learn legal research techniques with our study guide and become a proficient legal researcher.

  • Jurisprudence and Legal Theory


    All essential concepts, principles, and case law are included so that you can answer exam questions quickly.