Oliver Assersohn KC
Oliver Assersohn

Oliver Assersohn KC

Call: 2003 | Silk: 2024

"clearly outstanding"

Financial Services, Chambers and Partners

Oliver Assersohn KC is a leading financial services and commercial barrister. The independent legal directories for 2024 state :

  • Oliver is “incredibly intelligent and has a particularly effective written style. He is a real team player and can be depended on in high-stakes litigation” (Commercial Litigation, Legal 500 2024);
  • Oliver “brings commerciality as well as excellent analytical skills to the team” (Banking and Finance, Legal 500 2024);
  • Oliver is “client friendly” and “often in the high-profile, reported cases” (Financial Services, Chambers & Partners 2024); and
  • Oliver is a “go-to counsel for financial services regulatory matters” (Financial Services Regulation, Legal 500, 2024).

Previous entries in the directories over the years have included the following descriptions: first rate”, “clearly outstanding”, “an impressive advocate”,a robust advocate when needed”, “highly personable and a dream to work with”, a delight to work with and that he “will work tirelessly in support of the client’s case”.

Oliver is called to the Bar of England and Wales, undertakes offshore work and in Dubai is a registered DIFC (Part II) practitioner. Further details of Oliver’s areas of expertise, endorsements and publications are contained in the tabs below.

Areas of experience

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  • Arbitration

    Oliver is a member of the Swiss Arbitration Association and Associate Member of the Chartered Institute of Arbitrators. The nature of the work means that it necessarily must remain anonymous but some examples include:

    • Cengiz v Libya (ICC Arbitration, 2018): Case leader for Libya defending a US$302m claim for breaches of a bilateral investment treaty arising from the Arab Spring. Highly sensitive and complex legal issues regarding jurisdiction, breach and causation. Extensive and challenging cross-examination of 4 lay and 4 expert witnesses. Favourable outcome: parts of claim dismissed and award for US$51m cf. US$302m claimed.
    • Acting for a fund alleging breaches of a settlement deed with a former founder-director (matter successfully compromised).
  • Commercial Litigation

    Oliver’s commercial litigation experience is wide-ranging but is often centred on financial services related issues. Oliver has extensive experience of acting for parties in cases involving allegations of fraud, mis-sold investments, breach of contract and professional negligence.

    Examples of sample maters include:

    • Shop Direct v The Official Receiver [2023] EWHC Civ 367: Acted for the Claimant in this Part 8 claim involving complex questions of law regarding the interpretation of the FCA Handbook.
    • Akhmedova v Akhmedov & Ors: Instructed close to trial by son being sued by his mother for c. US$100m. Complex legal issues re the Insolvency Act (1986) and Matrimonial Causes Act (1973). Case highly sensitive and attracted significant press attention. As sole counsel, successfully argued at the search order return date that the propriety of the order should be examined at trial together with questions of costs (which the Claimant sought in the sum of £242,000) ([2020] EWHC 3006 (Fam)). Subsequent trial (led) [2021] EWHC 545 (Fam) (claim succeeded).
    • Liberty v Tancred [2018] EWHC 2707 (Comm): Claimants sole counsel in a 7-day trial of a preliminary issue concerning the sale of an IFA business. Complex legal issues regarding limitation. Demanding cross-examination and Claimant largely successful and awarded its costs.
    • Liberty v Tancred [2019] EWHC 2921 (Comm): Successfully obtained summary judgment. Complex arguments regarding construction, issue estoppel and res judicata.
    • Barons Finance Ltd v Barons Bridging Finance 1 Ltd & Ors [2018] EWHC 496 (Ch); [2019] EWCA Civ 2074: Claimant’s sole counsel at trial and in the Court of Appeal – in both, successfully argued an assignment of a loan book should be declared void on grounds of fraud (an insolvency case). Trial judge described case as “important and urgent”. A further challenge was that an imprisoned litigant in person Defendant could not attend the trial.
    • Oliver has represented numerous States and is presently acting for an African country seeking repatriation of Roman ruins taken to England in the 19th century.
    • Oliver also acted for a number of years for the second largest organisation in Ethiopia which successfully defeated a US$30m claim on grounds of forum non conveniens (Court of Appeal judgment, Mengiste v EFFORT & Ors [2017] EWCA Civ 1326).
  • Crypto and digital assets

    Oliver is co-author of the disputes chapter in Crypto and Digital Assets Law and Regulation published by Sweet and Maxwell in December 2023 and has advised in respect of various crypto related issues (e.g. in 2022, as to the viability of a range of potential claims against crypto-platforms).

  • Financial Services Regulation

    Oliver has practised in financial services law and regulation for 18 years following his secondment to the Regulatory Decisions Committee of the FCA (then FSA) which gave him an invaluable insight into how contested enforcement actions are approached. Since then, Oliver has acted in a number of the leading cases both in England and offshore. Oliver is a founder-member of the Financial Services Lawyers Association and heads the Executive Committee as well as publishing on various financial services matters (see publications).

    Examples of sample maters include:

    • FCA v a CEO (ongoing): Defending the former CEO of Carillion. The FCA’s case is that the former CEO was knowingly concerned in the company breaching various rules by making false statements to the market and failing to act with integrity. Case presently before the Upper Tribunal.
    • Shop Direct v The Official Receiver [2023] EWHC Civ 367: Acted for the Claimant in this Part 8 claim involving complex questions of law regarding the interpretation of the FCA Handbook.
    • FCA v Firm Z (2022): Advised listed company under severe time-restrictions if FCA’s interpretation of complex rules and objection to a very high value deal was correct and, if not the appropriate method of challenge.
    • Crypto-claims (2022): Advised as to viability of a range of potential claims against crypto-platforms.
    • Firm X v FCA (Regulatory Transactions Committee, Upper Tribunal, 2021): Successfully acted for firm in Upper Tribunal applications for suspension of FCA requirements and for privacy. If the applications had failed the consequences would have been catastrophic for the firm.
    • FCA v Firm Y (RDC, 2021): The FCA sought to impose an immediate variation of client’s permission which would have destroyed its business. Successfully persuaded the initial decision maker to change her mind thereby avoiding a disastrous outcome for client.
  • Insolvency
    • Barons Finance Ltd v Barons Bridging Finance 1 Ltd & Ors, Court of Appeal [2018] EWHC 496 (Ch) Acting for joint liquidator in respect of a declaration an assignment was void under s. 127 of the Insolvency Act 1986 (“IA”) and that it should be set aside under s. 238 and s. 423 of the IA.
    • X v Y (Chancery Division, August 2017) Acted for trustee in bankruptcy in obtaining an urgent freezing injunction before Mr. Justice Mann and instructed in the substantive underlying claim for breaches of the IA 1986.
    • X v Z (2016) Instructed on behalf of financial institution in bankruptcy proceedings against a debtor.
    • Akhmedova v Akhmedov & Ors, instructed close to trial by son being sued by his mother for c. US$100m. Complex legal issues re the Insolvency Act (1986) and Matrimonial Causes Act (1973). Case highly sensitive and attracted significant press attention. As sole counsel, successfully argued at the search order return date that the propriety of the order should be examined at trial together with questions of costs (which the Claimant sought in the sum of £242,000) ([2020] EWHC 3006 (Fam)). Subsequent trial (led) [2021] EWHC 545 (Fam) (claim succeeded).

Other information

  • Recommendations

    “He is great technically and is also very approachable and client-friendly.” “He is often in the high-profile, reported cases.” Financial Services, Chambers & Partners 2024

    ‘Oliver is an outstanding team player and brings commerciality as well as excellent analytical skills to the team. He is a go-to counsel for financial services regulatory matters.’ Financial Services Regulation, The Legal 500 2024

    Oliver is incredibly intelligent and has a particularly effective written style. He is a real team player and can be depended on in high-stakes litigation.’ Commercial Litigation, The Legal 500 2024

    ‘Oliver is an outstanding team player and brings commerciality as well as excellent analytical skills to the team.’ Banking and Finance, The Legal 500 2024

    “Oliver Assersohn is regarded very highly.” “He is very user-friendly and very experienced in financial services regulation.” “He is extremely knowledgeable about financial regulation in the UK and is clearly outstanding.” Financial Services, Chambers & Partners 2023

    “Oliver is very pleasant to work with and extremely personable. He is bright and committed; and understands how the FCA thinks. He is a robust advocate when needed.” Financial Services Regulation, Legal 500 2023

    “Technically brilliant, very hard working and a delight to work with.” Banking and Finance, Legal 500 2023

    Amiable and smart he produces superb written work and is a considered and impressive advocate. Wonderful to have in your team.” Commercial Litigation, Legal 500 2023

    “He’s technical but also sensitive to business and commercial implications – he weighs in in a way that furthers business goals.” “An ambitious and skilled advocate.” Financial Services, Chambers & Partners 2022

    “Oliver takes ownership of a case from the outset and will work tirelessly in support of the client’s case. He is very bright, and has significant FCA expertise.” Financial Services Regulation, Legal 500 2022

    “A superbly able junior, if there is an answer to a problem he will find it.” Banking & Finance, Legal 500 2022

    “Oliver has a rare mix of commercial acumen, empathy and wide-ranging communication skills which enable productive engagement at all levels.” Commercial Litigation, Legal 500 2022

    “An impressive specialist in FCA enforcement-related matters.” “He’s very responsive, very easy to deal with and the quality of his advice is also very good.” Financial Services, Chambers & Partners 2021

    “Highly personable and a dream to work with – slots into the team very well and a tremendous team player.” Banking & Finance, Legal 500 2021

    “Technically outstanding, and very hard working and responsive – he also has very sound client management (expectation management and empathy) skills.” Commercial Litigation, Legal 500 2021

    “Excellent attention to detail, good analytical skills coupled with regulatory knowledge and experience.” Financial Services, Legal 500 2021

    “He is easy to get along with and thorough in his advocacy, and pitches his arguments in a respectful way to the tribunal.” Oliver is “very accessible, very user-friendly and works really well as part of the team.” Financial Services, Chambers & Partners 2020

    “Very responsive and hardworking, his input is always measured and valuable”. Banking and Finance, Legal 500 2020

    Bright, well informed and has good judgement”. Financial Services, Legal 500 2020

    “A highly regarded junior who is an expert at handling complex issues relating to mis-sold investments and breaches of the perimeter. Having been on secondment to the FCA, he has highly valuable insight into the workings of the regulator….”Approachable, helpful and diligent.” “A credible and hard-working advocate.” Financial Services, Chambers & Partners 2019

    “Very good for fraud and financial regulatory investigations.” Financial Services, Legal 500 

    “Highly rated for banking and financial services disputes.” Banking and Finance, Legal 500

     “His written work is always excellent, he provides clear and practical advice and he deals with clients in a very empathetic manner.” Financial Services, Chambers & Partners 2017

    “Technically bright, hardworking, a team player and approachable.” Business and Regulatory Crime, Legal 500 2016

    “A truly excellent barrister, who knows the ins and outs of FCA regulations.” Banking and Finance, Legal 500 2016

    “A financial services and banking specialist who has a wealth of expertise in the area. He has a broad chancery and commercial practice…He is incredibly diligent and hard-working, and continues to impress with his technical knowledge.” Chambers & Partners 2016

    “He has a very innate feel for the regulators’ expectations and is very good at the detail. He understands the issues and is very diligent and analytical.” Chambers & Partners 2016

    “Very bright, exceptionally hardworking, personable and very practical. He really understands the FCA’s enforcement process.” Chambers & Partners 2015

    “He is calm, knowledgeable, diligent and keen to assist. A pleasure to work with.” Chambers & Partners 2015

    “Extremely well regarded for financial services and FCA regulatory issues.” “The barrister to go to with challenging issues.” Legal 500 2015

     “An absolute delight to work with.” Chambers & Partners 2014

     “Highly experienced in regulatory and FCA related matters.” Legal 500 2014

    “A financial services specialist.” Legal 500 2014

    “First rate.” Chambers & Partners 2013

    “An enviable reputation as a leading junior in financial services law.” Chambers & Partners 2012

    “The ‘knowledgeable, calm and authoritative’ Oliver Assersohn is recommended for contentious financial services work, where ‘his experience is almost unique’.” Legal 500 2012

    “Highly diligent.” Chambers & Partners 2011

    “Invaluable knowledge of the FSA disciplinary process.” Legal 500 2011

    “Understands how the regulator lives and breathes.” Chambers & Partners 2010

  • Publications
    • Co-author of the disputes chapter in Crypto and Digital Assets Law and Regulation (Sweet and Maxwell, December 2023).
    • Articles in numerous publications on financial services and banking matters (e.g. JIBFL November 2015 (the proposed EU Banking Union), JIBFL July/ August 2017 (Financial services law as a sword: cutting down contracts).
    • Co-author the chapter of COMBAR’s paper on Brexit (January 2017) entitled “MiFID, MiFID II and MiFIR: (1) Passporting and Equivalence Regimes; (2) Brexit effect on UK financial services dispute resolution” (December 2016).
    • Editor of the Decision Procedure and Penalties Manual Commentary in Butterworths Financial Regulation Service (c. 40,000 words) (published March 2015).
  • Lectures and seminars

    Oliver is regularly invited to give talks to solicitors firm and take part in panel discussions (for further details please contact Oliver’s practice management team by email to clerks@xxiv.co.uk).

  • Appointments & Memberships
    • Member of FSLA (founding member)
    • COMBAR
    • Associate member of Chartered Institute of Arbitrators.
    • Advocacy trainer for Middle Temple.
  • Awards
    • Queen Mother Fund Scholarship (2002)
    • Blackstone Entrance Exhibition (2002)
    • Queen Mother Fund Scholarship (2001)