William Day

William Day

Call: 2016

“Will is absolutely magnificent. He is particularly user-friendly, very hands-on, extremely bright and demonstrates equanimity on high-profile cases. He is something of an inspiration in court.”

- Chambers & Partners UK Bar (2024)

“His greatest strength is his considerable intellect, which is combined with evident confidence and enthusiasm. Like many of the very best barristers, his oral and written skills are equally strong.”

- Legal 500 UK Bar (2024)

“Will carries the expertise of a solicitor, the intellect of a legal academic, and all the strategic skills of a barrister.”

- Chambers & Partners UK Bar (2024)

“William is simply brilliant. He is fantastically bright, amazingly hard working and great to work with.”

- Legal 500 UK Bar (2024)

“Will must be one of the hardest-working and brightest juniors in his field. His ability to assimilate information quickly is extraordinary and he is technically first-rate.”

- Chambers & Partners UK Bar (2024)

Practice Overview

William is a versatile barrister with extensive interlocutory, trial, and appellate experience. His practice spans all aspects of commercial litigation and arbitration, with an emphasis on high value and high profile disputes. He has appeared in The Lawyer Top 20 Cases for 2022 and 2023.

William is ranked in the current editions of Chambers & Partners and the Legal 500 in commercial dispute resolution (“a fantastic advocate and legal adviser”), banking and finance (“one of the hardest working and brightest juniors in his field”), financial services (“a rising star who is always very responsive”), insurance (“simply brilliant. He is fantastically bright”), civil fraud (“fast becoming a go-to junior for high-value, multi-jurisdictional fraud cases”), and insolvency (“exceptionally well-regarded” and “just a natural”). He was shortlisted as Financial Services and Insurance Junior of the Year for the Legal 500 Bar Awards 2023, and was highlighted as a leading junior in Chambers and Partners’ ‘up-and-coming’ feature for the UK Bar Guide 2024.

William is noted in particular for his abilities as an advocate (“something of an inspiration in court”), the quality of his written work (“writes beautifully and can explain a case so a judge will want to find in your favour”), his intellectual strength (“has a brain the size of a planet”), dedication to his cases (“amazingly hard working and great to work with”), and his teamwork (“embodies team spirit. He absolutely gets it”).

William’s current and recent instructions include acting for Stonegate in a £1.1bn Covid-19 business interruption insurance claim; for investors in the £1.3bn Eclipse litigation; for joint liquidators in the $1bn asset tracing exercise against the Mehta family arising from the Winsome default; for a major Middle East bank in a $2bn fraudulent trading claim arising from the NMC Healthcare insolvency; and the Chedington Court Estate in a recent UK Supreme Court victory concerning standing to challenge officeholder decision-making.

William’s practice is focused on proceedings in the English courts but, in addition to regularly acting in international arbitration, William has been instructed in offshore proceedings including in the Bahamas, Dubai International Financial Centre, and the Abu Dhabi Global Market.

Alongside practice, William is an Associate Professor and Fellow in Law at Downing College, Cambridge (see here) where he teaches commercial law and other private law subjects. He has published widely on commercial law, and his work has been cited with approval by the Courts including in the Supreme Court’s landmark decisions in Pakistan International Airline Corp v Times Travel [2021] UKSC 40 and Barton v Gwyn-Jones [2023] UKSC 3.

William was previously a solicitor at Allen & Overy, where he worked on a range of commercial disputes with an emphasis on banking and finance litigation. He has also acted as a judicial assistant in the Chancery Division and has been seconded to the in-house litigation team at Credit Suisse.

William is regularly instructed led and unled to act in a range of high value and hard fought commercial disputes in the Commercial Court, the Chancery Division, the Commercial Circuit Court, in LCIA, ICC, SIAC and ICSID arbitrations, and offshore.

William’s commercial practice encompasses banking & finance, insurance, civil fraud and insolvency as set out in later sections. General commercial litigation experience also includes:

  • Middle East Real Estate v Lipton Rogers [2023] EWHC 1104 (Ch) – acting for defendant in £11m commission claim for the financing and development of 22 Bishopsgate (the tallest building in the City of London). Claim discontinued after a successful application for £1m in security for costs, with costs of the action awarded on the indemnity basis.
  • ICC Arbitration (2021-2023) – acting for leading Central European food manufacturer in €37m breach of tax warranty claim under share purchase agreement.
  • ICSID Arbitration (2020-2023) – acting for investor in Romania’s largest insurance company in claim against the Romanian state in connection with its special administration and liquidation.
  • LCIA Arbitration (2020) – acting for shareholder in well-known beverage company in private equity dispute arising from exercise of £15m put option.
  • Winlink v Liverpool FC [2020] EWHC 2271 (Comm) – acting for sports intermediary in dispute over commission in respect of £15m shirt sponsorship of Liverpool FC.
  • Davis & Co v Alam and Alam [2020] EWHC 3284 (Comm) – acting for claimant seeking injunctive relief and damages arising from acquisition of accountancy business.
  • Medenta Finance v Hitachi Capital [2019] EWHC 323 (Comm) and [2019] EWHC 516 (Comm) – expedited Commercial Court trial raising issues of interpretation, implication and rectification of restrictive covenants in financial brokerage agreement.
  • ICC Arbitration (2019) – acting for claimant in £4m gas field project dispute raising issues of termination, frustration, damages, and restitution for total failure of consideration.

William acts for policyholders in a variety of complex and market leading insurance claims, and has become a go-to junior for business interruption insurance claims following the COVID-19 pandemic.

Instructions include:

  • London International Exhibition Centre plc v RSA & Ors [2023] EWHC 1481 (Comm) – acting for major London conference and exhibition centre in £16m Covid-19 business interruption insurance claim. Listed for appeal in June 2024.
  • Liberty Retail & Ors v Liberty Mutual Insurance Europe & Ors (Commercial Court, ongoing) – acting for Regent Street department store in £18m Covid-19 business interruption insurance claim. Judgment awaited.
  • Bath Racecourse & Ors v Liberty Mutual Insurance Europe & Ors  (Commercial Court, ongoing) – acting for 16 racecourses in a £22m Covid-19 business interruption insurance claim. Judgment awaited.
  • Kaleidoscope & Ors v AIG (Commercial Court, ongoing) acting in group action for policyholders seeking to recover Covid-19 business interruption losses under ‘bomb hoax, bomb scare’ wording.
  • Stonegate v MS Amlin & Ors [2022] EWHC 2548 (Comm) – acting for UK’s largest pub owner in expedited £1.1bn Covid-19 business interruption insurance test case. Settled shortly before hearing in the Court of Appeal.
  • Re Mediterranean Insurance and Reinsurance Ltd (Companies Court, 2019-2021) – acting for administrators of an insolvent insurance undertaking with long tail liabilities seeking court directions to make distributions to creditors, and move into liquidation.

Before transferring to the bar, William was a specialist in banking and finance litigation, and financial services disputes as a solicitor at Allen & Overy. Since transferring to the bar, he has appeared for numerous banks including Deutsche Bank, RBS, NatWest, Lloyds, Barclays, Santander and HSBC in retail and commercial banking cases. He is also instructed by the Financial Conduct Authority on contentious financial services matters.

Experience includes:

  • NMC Healthcare v Dubai Islamic Bank [2023] ADGMCFI 0017 and [2023] ADGMCFI 0020 – acting for Dubai Islamic Bank in a $400m Islamic financing dispute in the Abu Dhabi Global Markets Court arising from the NMC Healthcare fraud.
  • Gurinov & Ors v Shaw & Ors (Chancery Division, ongoing) – acting for mezzanine lender in £7m leveraged property finance dispute. Listed for 9 day trial in 2025.
  • Investors in Eclipse v HSBC (Commercial Court, listed for 10 week trial in 2024) – acting for claimant group in a £1.3bn mis-selling claim against HSBC in connection with the Eclipse / Disney film finance schemes. See also [2022] EWHC 227 (Comm), [2022] Costs LR 325 and [2022] EWHC 1843 (Comm).
  • LCIA Arbitration (2022-2023) – acting for two leading Middle Eastern banks in a $500m dispute concerning security arrangements for sharia-compliant financings.
  • Financial Conduct Authority v Synergy Land Group [2023] EWHC 1130 (Ch) – acting for the FCA seeking directions for distribution of proceeds of enforcement action taken in respect of unauthorised collective investment scheme.
  • Heytex v Unity Trade Capital [2022] EWHC 2488 (Ch) – acting for claimant in dispute over international letter of credit arrangements and alleged exclusion of UCP 600 terms.
  • Tillman v Lloyds Bank and Better Capital (Commercial Court, settled) – defending Lloyds Banks in £150m claim by the former owner of the high street chain Jaeger arising from the circumstances of its administration.
  • AB Insolvency v Deutsche Bank (Central London County Court, settled before appeal to Chancery Division) – appeared for Deutsche Bank at trial in commission claim arising from hire of senior executive (unreported but see here).
  • Bankserve v Deutsche Bank (London Circuit Commercial Court, settled) – acting for Deutsche Bank defending claim from insurer broker seeking commission from role in settlement of dispute under asset finance agreements with prominent Greek shipowner.
  • Cyan Finance v Wilton Group (London Circuit Commercial Court, settled) – acting for claimant in £9m claim relating to defaults under in respect of advances under the Coronavirus Business Interruption Loan Scheme.
  • Banco San Juan v Petroleos de Venezuela [2020] EWHC 2937 (Comm), [2021] 2 All ER (Comm) 590 and [2021] EWCA Civ 610 – acting for Venezuela’s state-owned oil giant in $80 million dispute under credit agreements affected by US sanctions.
  • Financial Conduct Authority v 24HR Trading Academy [2020] EWHC 1455 (Ch), [2021] EWHC 648 (Ch) and [2023] EWHC 1130 (Ch) – acting for the FCA in claim for breach of the general prohibition based on unauthorised investment advice and investment arrangements, including obtaining ex parte a freezing order, and directions for distribution of proceeds of enforcement action.
  • Credit Suisse Asset Management v Titan 2006-1 [2016] EWHC 969 (Ch) and [2016] EWCA 1293 – at Allen & Overy, acting for defendant cash manager and agent bank in securitisation note dispute.
  • Metlife v JP Morgan Chase Bank [2015] EWHC 463 (Comm) and [2016] EWCA Civ 1248 – at Allen & Overy, acting for the defendant bank in dispute over inflation-linked bonds.

Much of William’s practice involves disputes at the cross-over between finance, fraud and insolvency. He has a wide-ranging experience of commercial fraud cases, including acting led and unled in a number of applications for freezing and prohibitory injunctions and search orders.

Experience includes:

  • Joyvio Group & Ors v Moreno & Ors (Commercial Court, ongoing) – acting for Chinese food conglomerate in $1bn fraud claim arising from acquisition of Chilean salmon farm business.
  • Boettcher v Xio & Ors [2023] EWHC 801 (Comm) and [2023] EWHC 1163 (Comm) – acting for former global head of value creation in claim against a fund and its partners for alleged misrepresentations as to the nature of the fund and its investor base.
  • Manek v 360 One WAM & Ors [2023] EWHC 710 (Comm) and [2023] EWHC 985 (Comm)– acting for Indian financial services company defending £50 million claim relating to sale of Indian payments company Hermes to Wirecard.
  • Harrington & Charles & Ors v Mehta & Ors [2022] EWHC 2960 (Ch) and [2023] EWHC 2420 (Ch) – acting for liquidators in a US$1bn asset tracing exercise from an alleged fraudulent default under precious metals facilities.
  • Guy v Foster (Chancery Division, ongoing) – acting for purchaser of rural estate and wedding business in Dorset in £18m deceit claim against seller.
  • Banque Havilland v Mazurier & Ors (Supreme Court of the Bahamas, settled) – $10m fraud claim to rescind various business introducer agreements allegedly entered into in breach of fiduciary duty.
  • Aggreko v Sumitomo Mitsui Banking Corp & Ors (Commercial Court, 2020, unreported, but see press here) – acting for claimant in $37 million claim against a Yemeni electricity company. Injunctive relief obtained preventing payment out under fraudulent call on performance bonds in support of DIFC-LCIA arbitral proceedings.
  • CMOC Sales and Marketing v Persons Unknown [2018] EWHC 2230 (Comm) – as a pupil assisting Philip Hinks, in claim in conspiracy and knowing receipt claim by corporate victim of $10million cyber fraud against persons unknown

William’s experience encompasses liquidations, administrations and bankruptcies, including not only bankruptcy and winding up petitions, but also applications to challenge officeholder decisions, to reverse transactions at an undervalue, to restore companies to the register at Companies House, and to access a company’s register of members. William also has been instructed in restructuring matters, including schemes of arrangement.

Experience includes:

  • Re NMC Healthcare Ltd (Abu Dhabi Global Markets Court, 4 week trial listed for 2024) defending major Middle Eastern bank in $2bn fraudulent trading claim arising from the NMC Healthcare insolvency.
  • Brake v The Chedington Court Estate [2023] UKSC 29, [2023] 1 WLR 3035; [2022] EWCA Civ 1302, [2022] EWCA Civ 235 and [2020] EWCA Civ 1491, [2021] BusLR 577; see also [2020] EWHC 1810 (Ch), [2020] 4 WLR 113; [2021] EWHC 670, [2021] 4 WLR 71 and [2021] EWHC 671; [2021] EWHC 2308 (Ch); and [2023] EWHC 1560 (Ch) – acting in related bankruptcy and partnership liquidation proceedings, now leading authorities on standing to make insolvency applications, on section 283A of the Insolvency Act 1986, on unfair prejudice in the context of standalone moratoriums, and on rights of confidence/privacy in the insolvency context.
  • Patley Wood Farm v Kicks [2023] EWCA Civ 901, [2022] EWHC 2973 (Ch), [2022] EWHC 3118 (Ch) and [2022] EWHC 3257 (Ch) – acting for creditors challenging trustee in bankruptcy decision-making as perverse.
  • Re Morses Club [2023] EWHC 705 (Ch) – acting for customer advocate at directions hearing in scheme of arrangement of doorstep loans provider.
  • Re ALL Scheme [2022] EWHC 549 (Ch) and [2022] EWHC 1318 (Ch) – acting for customer advocate at directions and sanctions hearing in £112m scheme of arrangement of consumer finance group, Amigo.
  • Re Harrington & Charles Trading Co Ltd [2021] EWHC 1566 (Ch) – acting for an investment bank in a US $1bn multi-jurisdictional asset tracing exercise through UK shell companies in liquidation/dissolution.
  • Re Core VCT plc [2020] EWCA Civ 1207, [2021] PNLR 10 and [2019] EWHC 540 (Ch) and [2019] EWHC 701 (Ch) – acting for liquidators of private equity funds resisting an application for removal from office, and obtaining information and documents from third parties under section 234 to 236 of the Insolvency Act 198. Now the leading authority on members’ voluntary liquidations.
  • Re Mediterranean Insurance and Reinsurance Ltd (in administration) (2019-2021) – acting for administrators of an insolvent insurance undertaking long tail liabilities seeking court directions to make distributions to creditors, and move into liquidation.
  • Re Asia Resource Minerals plc (PS/2015/15) – at Allen & Overy, acting for an investment bank in respect of Takeover Panel proceedings over a concert party reverse takeover.

William has a particular interest in the conflict of laws, and receives regular instructions on complex jurisdictional and choice of law matters. He won the John Morris Prize for best performance in the subject in his postgraduate studies at Oxford, and has also published on topical jurisdiction and choice of law issues.

Experience includes:

  • Joyvio Group & Ors v Moreno & Ors (Commercial Court, ongoing) – acting for Chinese food conglomerate in $1bn fraud claim arising from acquisition of Chilean salmon farm business. Jurisdiction challenge to be heard in June 2024.
  • Boettcher v Xio & Ors [2023] EWHC 801 (Comm) and [2023] EWHC 1163 (Comm) – acting for claimant in jurisdiction challenge in litigation against a fund and its partners for alleged misrepresentations as to the nature of the fund and its investor base.
  • Manek v 360 One WAM & Ors [2023] EWHC 710 (Comm) and [2023] EWHC 985 (Comm)– acting for Indian financial services company in jurisdiction challenge to £50 million claim relating to sale of Indian  payments company Hermes to Wirecard.
  • Harrington & Charles & Ors v Mehta & Ors [2023] EWHC 307 (Ch) acting for liquidators in jurisdiction challenge to continuation of fraud claim in England against the Mehta family arising from the Winsome default in India.
  • RBS v Schommer (London Circuit Commercial Court, settled) – acting for claimant in jurisdiction challenge in litigation arising out of default under loan agreement.
  • Banco San Juan v Petroleos de Venezuela [2020] EWHC 2937 (Comm), [2021] 2 All ER (Comm) 590 and [2021] EWCA Civ 610 – acting for Venezuela’s state-owned oil giant in $80 million dispute about the effect of foreign law illegality at common law (the ‘Ralli Bros’ rule) and under the Rome I Regulation on English law credit agreements.
  • Anon (2020) – advising international auction house on potential liability regarding artwork allegedly stolen by the Nazis in the Second World War, raising issues of applicable law for liability and limitation for conversion, negligence and breach of contractual terms.
  • SIAC Arbitration (2018) – acting on an arbitration concerning issues of proof of foreign law and recognition of foreign judgments.
  • Marme Inversiones v RBS & Ors [2016] EWHC 1570 (Comm) – at Allen & Overy, acting for the second to fifth defendants in jurisdiction challenge involving lis pendens and interface between the Brussels Regulation and the Insolvency Regulation.
  • Plaza v Law Debenture [2015] EWHC 43 (Ch) – as judicial assistant to Proudman J, a jurisdiction challenge involving reflexive effect of provisions of the Brussels Regulation.
Winner: UK Bar Awards 2023
The Lawyer Awards 2022: Chambers of the Year