Mark O’Neill
Team Leader
+44 (0)20 7842 3777
Click here to email
Call 2007
"He is very bright, passionate and drafts very well. He is punchy." "He is very responsive, user-friendly, very bright, and his drafting is excellent and concise."
Chambers & Partners
Mark O’Neill
Team Leader
+44 (0)20 7842 3777
Click here to email
Jamie Thomas
Team Leader's Assistant
+44 (0)20 3873 6851
Click here to email
Adam Sher practices across a broad range of practice areas and is particularly recognised for his expertise in all aspects of banking work, having been involved in many of the leading disputes in that field in recent years.
He is recognised in the leading legal directories, having been ranked for many years at Tier 1 in both Chambers and Partners and Legal 500 for Banking & Finance work. He was recently described as “an absolute standout in the field. He’s fiercely bright, across the details and very client-friendly” and as a “very robust advocate” and “great cross-examiner” who is “loved by clients for his enthusiasm and dedication to his cases”.
He has been nominated three times for ‘Banking Junior of the Year’ at the Chambers UK Bar Awards (in 2016, 2017 and 2023), winning in 2017.
Civil fraud claims (including cases concerning breach of fiduciary duty, bribery, deceit, conspiracy forgery and breach of trust) also form an increasing part of Adam’s practice, as do insurance and reinsurance related matters (acting for both for insurers and insureds), including the mammoth Russian Aircraft claims.
Adam also has a particular interest in all aspects of legal professional privilege, having been involved in a number of important decisions in this area, and frequently speaks and writes on this topic. He is a contributor to the forthcoming fourth edition of the leading practitioner text on legal privilege, edited by Bankim Thanki KC and due to be published in 2025.
Much of Adam’s work has an international dimension, and he has been instructed in matters before courts or arbitral tribunals in The Bahamas, Gibraltar, Guernsey, Abu Dhabi, Singapore and the BVI.
He is also frequently involved in cases before the appellate courts, including the Court of Appeal and Supreme Court.
Russian Aircraft
Acting with James Cutress KC, Simon Paul and Ian Bergson for AIG Europe SA (in its capacity as a war risk insurer) in this mammoth multi-billion dollar dispute arising from the non-return of hundreds of aircraft leased to Russian airlines following the full-scale invasion of Ukraine by Russia in February 2022, and the subsequent economic sanctions. The case was one of The Lawyer’s “Top 20” cases of 2024. A 12-week trial of the action is being heard before Butcher J and is scheduled to conclude by the end of 2024.
Loreley Financing (Jersey) No 30 Ltd v. Credit Suisse [2023] EWHC 2759 (Comm)
Acting with Paddy Goodall KC, Laurie Brock and Marcus Field for Credit Suisse in this long-running case arising from the sale of a CDO linked to RMBS in 2007, which was one of The Lawyer’s “Top 20 Cases” of 2023. The buyer (an SPV set up by IKB, a German bank) made wide-ranging allegations of fraud concerning Credit Suisse’s RMBS business, based upon a large number of allegedly implied representations. The claims against Credit Suisse were dismissed in their entirety after a 9-week trial and Credit Suisse was awarded indemnity costs for the entire action. Cockerill J’s judgment (following her earlier decision in Leeds City Council v Barclays, in which Adam also acted) is now the leading authority analysing how the reliance test applies to implied representations.
Loreley Financing (Jersey) No 30 Ltd v. Credit Suisse [2022] EWCA Civ 1484, [2023] 1 WLR 1425
Led by Tamara Oppenheimer KC in the Court of Appeal successfully upholding the first instance ruling of Mr Justice Robin Knowles in an important dispute concerning whether the identity of the party giving instructions is itself subject to legal professional privilege.
Leeds City Council & Ors v Barclays Bank [2021] QB 1027
Led by Adrian Beltrami KC for Barclays in two sets of proceedings brought by local councils seeking rescission of hundreds of millions of pounds of “Lender Option Borrower Option” (“LOBO”) loans relying on alleged implied representations based on LIBOR misconduct. The judgment of Mrs Justice Cockerill, striking out the claims, is the leading authority in this area. The proceedings were compromised shortly before the hearing of an appeal in early 2022.
Sports Direct International v Financial Reporting Council [2020] EWCA Civ 177, [2020] 2 WLR 1256
Acting (led by Richard Lissack KC) for SDI in an important appeal concerning legal professional privilege in the context of professional regulatory investigations in which the Court of Appeal allowed SDI’s appeal, confirming the absolute nature of legal professional privilege and rejecting the existence of a so-called “no infringement” exception.
Much of Adam’s practice is banking/finance related, covering the full spectrum from investment banking and investment management to private and retail banking, with previous and present clients including VTB Capital, Credit Suisse, Barclays, Bank of Scotland, NatWest / The Royal Bank of Scotland, Bank of America Merrill Lynch, Deutsche Bank, CA-CIB (formerly Calyon), Julius Baer, HSH Nordbank, ING Bank, CaixaBank and Nomura. Adam was Chambers & Partners ‘Banking Junior of the Year’ in 2017 (having also been nominated for that award in 2016 and 2023). He has particularly deep experience of LIBOR/EURIBOR related claims, having acted in most of the leading civil cases in that area and in claims arising from implied misrepresentations.
FDIC-R v Barclays, NatWest Markets & Ors
Instructed (with Robert O’Donoghue KC and Laurie Brock) by NatWest in connection with these competition law proceedings brought by an arm of the US Government as receiver for a number of failed banks against seven major banks and the British Bankers Association alleging collusive LIBOR “lowballing”. The Financial List proceedings (which were commenced in 2017) are listed for a 19-week trial commencing in February 2026.
M1 Capital and M1 Limited v Credit Suisse
Acting with Richard Handyside KC in defending Credit Suisse in the prime brokerage claim brought by a hedge fund arising from the sale of shares by Credit Suisse following a margin call during the market turmoil caused by the COVID-19 pandemic. A trial is listed for November 2025.
Various SAM Borrowers v Bank of Scotland
Acted (with Richard Handyside KC) for Bank of Scotland in an important test case concerning the ‘unfair relationship’ provisions of the Consumer Credit Act. The highly-publicised group claim (by over 160 claimants) arose from so-called ‘shared appreciation mortgages’ sold in the late 1990s (and pursuant to which the borrowers agreed to pay a percentage of the increase in the value of their house to the bank in exchange for reduced or zero interest rates for life). The case settled very shortly before trial in January 2024.
Vestia v Nomura
Acted (with Richard Handyside KC) for Nomura in substantial claims arising from derivatives transactions with a Dutch housing authority, raising in particular questions of capacity. The claims were listed for a 6-week trial in 2025, but were settled.
Leeds City Council & Ors v Barclays Bank
Acting with Adrian Beltrami KC for Barclays in defending LIBOR-manipulation based misrepresentation claims brought by a number of local authorities who had entered into long term lending with Barclays. Barclays succeeded in a strike-out application against the local authorities on the grounds that they had not been aware of the implied representations relied upon.
Marme Inversiones v RBS, HSH, BayernLB, ING & La Caixa
Acting (with Tim Howe KC) for four banks in successfully defending claims for rescission and damages arising from alleged EURIBOR manipulation.
Property Alliance Group v RBS
Instructed for RBS throughout (led at various times by David Railton KC, David Foxton QC and then Richard Handyside KC and Paul Sinclair KC) these important financial List proceedings, which resulted nine interlocutory judgments (including multiple decisions relating to legal professional privilege), a 10-week trial before Asplin J and seven-day appeal before the Court of Appeal, where the dismissal of all claims against RBS was upheld. ([2016] EWHC 3342 (Ch), [2018] EWCA Civ 355, [2018] 1 WLR 3529).
Deutsche Bank v Unitech
Acting (with a series of leaders, Mark Hapgood QC, Tim Howe KC and Sonia Tolaney KC) for DB in this long-running litigation including (among others) claims arising relating to LIBOR manipulation. The case went twice to the Court of Appeal on interlocutory claims before concluding with a judgment after trial in DB’s favour in 2019.
Italian Swaps litigation
Acting, over the past 15 years, in numerous cases arising out of derivative transactions entered into between international banks (including in particular Bank of America Merrill Lynch and Nomura International) and various Italian local authorities including Merrill Lynch v Verona, Merrill Lynch v Florence and Merrill Lynch v Milan.
Barclays v Borkhatria
Acting (as sole counsel) for Barclays in a successful summary judgment application in relation to a claim on a personal guarantee raising wide-ranging issues including economic duress, breaches of duties of disclosure in the context of guarantees and misrepresentation.
WW Property Investments v NatWest
Acting (with Andrew Mitchell KC) for NatWest, successfully striking out a case that the bank owed a duty of care to a customer taking part on the Interest Rate Hedging Review programme. The decision was upheld by the Court of Appeal in a conjoined appeal (with CGL v RBS).
Stuart Wall v RBS
Instructed (with Andrew Mitchell KC, Jeremy Goldring KC, James Cutress KC, Tamara Oppenheimer KC and Laurie Brock) for RBS to defend a £700 million claim concerning an abortive CMBS transaction and involving allegations concerning RBS’s GRG division and LIBOR manipulation. The case (one of The Lawyer’s ‘Top 20 Cases of 2017’) settled shortly before a 12-week trial in 2017.
Joyvio Group and ors v Isidoro Ernesto Quiroga Moreno and ors
Acted (with Bankim Thanki KC and Paul Sinclair KC) for the defendants in a US$1 billion fraud claim arising from the sale by the defendants of a Chilean salmon-farming business to the Claimant Chinese agribusiness giant. The defendants were successful in challenging the jurisdiction of the English Courts leading to a stay in favour of the Chilean Court: see [2024] EWHC 2493 (Comm).
VTBC v Republic of Mozambique
Acted (with David Railton KC, Timothy Howe KC and Ian Bergson) for VTBC Capital in multiple proceedings in the Commercial Court arising from the so-called “hidden loans” controversy involving in excess of $2 billion of debt guaranteed by the Republic of Mozambique.
Confidential Arbitration (SCC)
Acting (with Tim Howe KC) in a substantial confidential SCC arbitration in connection with 20+ claims involving allegations of fraud, breach of fiduciary duty, forgery and bribery.
Between 2017 and 2019, acting (with David Mumford KC) for two Ukrainian businessmen in a substantial dispute involving allegations of forgery, sham trust, dishonest assistance and conspiracy. The case raised a wide range of legal issues on interlocutory applications including relation to the proper scope of proprietary injunctions, the powers of receivers and access to their documents, as well as issues relating to champerty and litigation funding.
Previously acting (with Michael McLaren KC) in proceedings brought against English solicitors alleging conspiracy resulting in the fraudulent misappropriation of $17.5 million of client money.
Adam is instructed in a wide range of commercial disputes, frequently as part of a large counsel team but also often alone. Many of his cases involve international elements, and questions of jurisdiction and the management of multiple proceedings are a frequent feature.
Joyvio Group and ors v Isidoro Ernesto Quiroga Moreno and ors
Acted (with Bankim Thanki KC and Paul Sinclair KC) for the defendants in a successful jurisdiction challenge in relation to this US$1 billion claim arising from arising from the sale by the defendants of a Chilean salmon-farming business: see [2024] EWHC 2493 (Comm).
Onecom Partners v Palmer
Acting (with Leah Gardner) for the Claimant telecommunications company in a warranty dispute arising out of a business sale. Adam successfully defeated a strike out/summary judgment application brought on limitation grounds: [2023] EWHC 1393 (Comm) (Henshaw J). The proceedings remain ongoing.
VW NOx Emissions Group Litigation
Acted (with Charles Gibson KC, Prashant Popat KC, Brian Kennelly KC, Geraint Webb KC, Kathleen Donnelly KC, Nicholas Sloboda and Thomas Evans) for VW in relation to claims brought arising from the “Dieselgate” scandal. Adam was instructed specifically to address claims in implied representation/deceit, which were the subject of a strike out application heard by Waksman J in late 2021: see Crossley v Volkswagen [2021] EWHC 3444 (QB).
VTBC v Republic of Mozambique
Acted for VTBC in multiple proceedings against Republic of Mozambique arising from so-called “hidden loans” controversy and raising wide-ranging issues, including in connection with sovereign immunity.
FDIC-R Litigation
Instructed (with Robert O’Donoghue KC and Laurie Brock) by NatWest in connection with these competition law proceedings brought by an arm of the US Government as receiver for a number offailed banks against seven major banks and the British Bankers Association alleging collusive LIBOR “lowballing”. The Financial List proceedings (which were commenced in 2017) are listed for a 19-week trial commencing in February 2026.
Barclays v ENPAM
Acted (with Sonia Tolaney KC) for Barclays in a claim against an Italian pension fund for breach of an exclusive jurisdiction clause and the application of the lis pendens rules under the Judgments Regulation, at both first instance (Blaire J) and before the Court of Appeal.
Marme Inversiones v NatWest Markets & Ors
Acted (with Tim Howe KC and Simon Atrill) in the jurisdiction battle phase over this dispute which raised issues as to the relationship between the jurisdiction provisions of the Judgments Regulation and the Insolvency Regulation.
NZ Super v Novo Banco
Acted (with Laurence Rabinowitz KC and Tom Smith KC) at first instance for the claimants in a jurisdiction battle over claims against a Portuguese “Bridge Bank”.
GMR v Government of the Maldives
Arbitration in Singapore under UNCITRAL rules. Acting (with Bankim Thanki KC) for Indian infrastructure giant GMR in its $1.3 billion claim against the Republic of the Maldives relating to the repudiation by the Maldives Government of a concession agreement to operate and develop Mále International Airport.
Glencore v Total
Acted (with Patrick Goodall KC) for Total in a claim brought against it by Glencore in respect of a delivery (or lack of delivery) of petroleum product in Kenya.
An increasing feature of Adam’s practice is the occurrence of contentious questions of privilege, with a particular emphasis on claims to privilege in the context of regulatory investigations, a subject on which he has lectured.
He has also acted as an “independent reviewer” in a privilege dispute, providing advice and assistance to a law firm conducting a review, and issuing decisions on disputes when they arose.
Loreley Financing (Jersey) No 30 Ltd v. Credit Suisse [2022] EWCA Civ 1484, [2023] 1 WLR 1425
Led by Tamara Oppenheimer KC in the Court of Appeal successfully upholding the first instance ruling of Mr Justice Robin Knowles in an important dispute concerning whether the identity of the party giving instructions is itself subject to legal professional privilege.
Financial Reporting Council v Sports Direct International
Acted (with Richard Lissack KC) for Sports Direct International at first instance and before the Court of Appeal in an action brought by the Financial Reporting Council (the accountancy regulator) which raised important issues of privilege issues arising from a regulatory investigation in which documentary requests were made of it as a witness. In early 2020, the Court of Appeal overturned Arnold J’s decision and rejected the existence of any so-called “no infringement” exception.
A v (1) B & (2) Financial Reporting Council
Acted (with Richard Lissack KC) for ‘A’ in Part 8 proceedings arising from an investigation by the FRC, addressing the proper approach in relation to disputes between a regulated entity and its client over documents over which the client claims legal professional privilege.
PAG v RBS
Acted in the long-running dispute (see above under Banking & Finance) involved numerous interlocutory applications and a series of judgments from Birss J and Snowden J on matters including the scope of the “without prejudice” privilege, limited/selective waiver, collateral waiver, the scope of so-called “waiver by pleading” and claims to litigation privilege over secretly taped interviews procured by dishonesty. An appeal from the first decision of Birss J, in which the FCA intervened in respect of the “without prejudice” communication issue, was compromised shortly before hearing in the Court of Appeal.
RBS v Cooke, Young & Keidan LLP
Acted (with Patrick Goodall KC and Laurie Brock) for RBS in urgent injunctive proceedings against Cooke, Young & Keidan LLP (the then-solicitors for Property Alliance Group) concerned with the obligations on firms to protect confidential information received by or in possession of an employee of the firm as a result of his prior employment.
Russian Aircraft
Acting with James Cutress KC, Simon Paul and Ian Bergson for AIG Europe SA (in its capacity as a war risk insurer) in this mammoth multi-billion dollar dispute arising from the non-return of hundreds of aircraft leased to Russian airlines following the full-scale invasion of Ukraine by Russia in February 2022, and the subsequent economic sanctions. The case was one of The Lawyer’s “Top 20” cases of 2024. A 12-week trial of the action is being heard before Butcher J and is scheduled to conclude by the end of 2024.
Confidential Arbitration
Acted with John Lockey KC and Ben Parker for an insurer in a dispute with its reinsurers concerning the settlement of very substantial ($500m+) property claims arising out of property damage in Chile.
Confidential Arbitration (LCIA)
Acted with James Cutress KC for the insured in relation to a dispute under a credit insurance policy.
Confidential Arbitration (LCIA)
Acted with James Cutress KC for insurers in relation to a dispute under a trade credit insurance policy including issues relating to non-disclosure, breach of warranty and late notification.
Confidential Arbitration (LCIA)
Acted with David Railton KC and James Cutress KC for insurers in a substantial ($200 million) arbitration which concerned to coverage under a financial institutions crime and civil liability policy.
Advising (as part of a team of counsel lead by Mark Simpson KC) insurers in connection with a £50 million+ aggregation dispute arising from the Innovator litigation.
Instructed (with Patricia Robertson KC) by a Guernsey-based fund administrator and its former directors in connection with a high-value claim for negligence and breach of fiduciary duty arising from the high-profile failure of the Arch Cru investment funds.
Acted for the claimant in a claim before the Gibraltar Courts against an independent financial advisor for negligent advice.
Acted (with Mark Simpson KC) for a firm of accountants in relation to a professional negligence claim in relation to tax advice.
Acted (with Bankim Thanki KC) for a law firm in proceedings in The Bahamas in respect of a claim for professional negligence arising from a conveyancing transaction.
Appointments
Prizes
Mark O’Neill
Team Leader
+44 (0)20 7842 3777
Click here to email
Jamie Thomas
Team Leader's Assistant
+44 (0)20 3873 6851
Click here to email
Appointments
Prizes