Katherine Ratcliffe

Professional practice

Katherine has a broad practice spanning commercial litigation, international arbitration (international investment treaty claims and international commercial arbitration), and public international law, as well as related areas of public and human rights law. She is recognised by the Legal 500 as a ‘Rising Star’ in (1) International Arbitration, (2) Commercial Litigation and (3) Civil Fraud and described as “far beyond her call” and “a real star”.

Katherine is regularly instructed on high-profile and high-value commercial disputes, particularly concerning civil fraud and asset recovery, banking and other financial litigation, and professional negligence. Katherine’s investor-state and international commercial arbitration experience includes proceedings under the LCIA, PCA, SCC and UNCITRAL Rules, as well as enforcement of and challenges to arbitral awards. Alongside her commercial and investor-state practices, Katherine also has a practice in public international law, which includes acting in matters concerning State immunity issues, human rights, sanctions, and international anti-corruption and asset recovery mechanisms.

Highlights of Katherine’s recent or current work before domestic courts include:

NMC Health plc v EY: one of The Lawyer’s Top 20 cases of 2025, a $2.5bn claim by the holding company of a Gulf-based healthcare group arising out of a fraud allegedly perpetrated by its majority shareholders and senior management.
Czech Republic v Diag [2024] EWHC 503 (Comm) and [2024] EWHC 2102 (Comm): one of The Lawyer’s Top 20 cases of 2024, concerning ss 67 and 68 challenges in the Commercial Court, as well as an application for security for an award heard by the Court of Appeal ([2023] EWCA Civ 1518).
WWRT Ltd v Zhevago [2024] EWHC 122 (Comm): jurisdiction challenge in the Commercial Court, involving consideration of the impact of the Ukraine war on the functioning of the Ukrainian legal system.
Navigator Equities Ltd v Deripaska [2023] EWHC 788 (Comm): long-running committal proceedings which were ultimately dismissed following a three day trial in 2023 in the Commercial Court.
E D & F Man Capital Markets Limited v Come Harvest Holdings Limited & Ors [2022] EWHC 229 (Comm) and [2022] EWCA Civ 170: a deceit and conspiracy claim arising out of the provision of forged warehouse receipts in a repo transaction for the sale and repurchase of nickel.
Republic of Mozambique v Credit Suisse & Ors: Commercial Court proceedings in respect of a purported sovereign guarantee allegedly procured by bribery.

In addition to appearing as junior counsel, Katherine regularly appears unled in the High Court (Chancery Division and Commercial Court), as well as in the County Court.

What Others Say

The Legal 500 2025, Commercial Litigation:

“She punches well above her years of call. Her drafting is persuasive and succinct.”

The Legal 500 2025, Fraud Civil:

“A real star who performs far beyond her call.”

The Legal 500 2025, International Arbitration:

“Katie is a pleasure to work with. She is legally and procedurally sharp, and her analysis skills are on point.”

The Legal 500 2024, Commercial Litigation:

“Katherine is an excellent junior barrister – her skills are far beyond her years of call. Her case analysis and drafting skills are of the highest standard, and she is, quite rightly, very highly in demand.”

The Legal 500 2024, Fraud Civil:

“Katherine is very responsive and gives clear, thought-out advice. She grasps issues very quickly and is calm under pressure.”

Arbitration & related court applications

Katherine has substantial experience in both commercial and investor-state arbitrations, under a wide variety of arbitral rules (e.g. LCIA, PCA, SCC, UNCITRAL and ICSID) and in related domestic court proceedings. Her experience is recognised by directory rankings which describe her as being “a pleasure to work with”, “legally and procedurally sharp” and with analysis skills “on point”.

Investor-State arbitrations

A claim brought by a multi-sector investor in a State of the Caucasus region, under a bilateral investment treaty. The claim particularly raised issues relating to excise duties, national competition law, enforcement of revenue law, and the application of most favoured nation provisions. Led by Sam Wordsworth KC and Lucas Bastin KC.
A claim brought by an investor in Belize, under a bilateral investment treaty. The claim arose out of an infrastructure project and raised issues as to the application of the fair and equitable treatment standard and less favourable treatment provisions. Led by Angeline Walsh KC.
Advised on a potential denial of justice claim by an investor under a bilateral investment treaty.
Advised on the scope of the police powers doctrine as an exception to the requirement of compensation for lawful expropriation.
Advised on potential investment treaty claims against a government in respect of a bilateral investment treaty which provided that an arbitration would only take place if the parties subsequently gave their consent.

Commercial arbitrations

An LCIA arbitration on behalf of a company, involving allegations of breach of fiduciary duty.
An LCIA arbitration on behalf of an insurance company, defending an unjust enrichment claim and a coverage dispute.
An arbitration on behalf of American insureds in relation to a coverage dispute with P&I insurers and excess insurers, involving allegations of material misrepresentation and non- disclosure. Led by Paul Stanley KC and Jeremy Brier KC.
A commercial arbitration under the JAMS International Arbitration Rules for a claimant in a claim arising out of breaches of a securities loan agreement and involving allegations of force majeure, penalty clauses and relief from forfeiture. Led by Jeremy Brier KC.

Court applications

Czech Republic v Diag [2024] EWHC 503 (Comm) and [2024] EWHC 2102 (Comm): one of The Lawyer’s Top 20 Cases of 2024. Successfully resisted an application for permission to appeal to the Court of Appeal on security for an award: [2023] EWCA Civ 1518.
Assisted with an application for an interim injunction under s.44 of the Arbitration Act 1996 to prevent a lender from wrongfully taking collateral under a securities loan agreement.
Assisted with resisting a s.103 challenge to an order enforcing an investment treaty arbitral award which raised issues of estoppel and waiver.
Assisted with resisting a s.103 challenge relating to whether there was a written arbitration agreement between the parties. The case raised complex issues including issues as to the applicable law and public policy grounds for refusing to enforce an arbitral award.
Katherine also recently published an article with Professor Paul Davies on anti-arbitration injunctions and s 9 Arbitration Act 1996 stays: ‘Anti-Arbitration Injunctions and Stays to Arbitration: Sodzawiczny v Smith’ [2024] LMCLQ 380.

Banking & financial services

E D & F Man Capital Markets Limited v Come Harvest Holdings Limited & ors [2022] EWHC 229 (Comm): Acted (led by Huw Davies KC) for the successful claimant in Commercial Court proceedings arising out of the provision of forged warehouse receipts in a “repo” transaction for the sale and repurchase of nickel. The case was heard over five weeks in 2021 and the trial involved expert evidence in the field of market practice in metal repurchasing transactions.
Advised on potential events of default under sovereign debt bonds and the ramifications of an event of default being triggered for a State.
Advised a bank on the impact of sanctions on Russian entities in respect of loan agreements. Advised as sole counsel on the circumstances in which an all monies guarantee can be varied.
Katherine recently assisted with editing the volume of Atkin’s Court Forms on guarantees and provided research assistance on consumer credit transactions, performance bonds, bank guarantees, letters of comfort, and the law surrounding contracts of suretyship for the 8th
Edition of Andrews & Millett on Guarantees (forthcoming). Katherine has also recently written an article on the limitation period for interest rate swaps: ‘The classification of interest rate swaps as contingent liability cases’ (2022) 7 JIBFL 468.

Civil fraud & asset recovery

Katherine is identified as a “Rising Star” by Legal 500 in Civil Fraud and has been described as “A real star who performs far beyond her call.” Katherine has considerable experience of the full range of issues which arise in civil fraud litigation, having been seconded to the civil fraud team at RPC for five months in 2021, as well as instructed more recently on a number of high-profile and high-value matters. Recent cases include:

NMC Health Plc v EY: defending EY in one of The Lawyer’s Top 20 cases of 2025 concerning a claim for USD 2.5 billion by the holding company of a Gulf-based healthcare group, arising out of a fraud allegedly perpetrated by its majority shareholders and senior management.
Navigator Equities Ltd v Deripaska [2023] EWHC 374 (Comm): Acted (led by Thomas Grant KC and Anna Dilnot KC) for the defendant in an application for committal for alleged contempt of court for breach of an undertaking. The Commercial Court ultimately dismissed the application as the Claimants had failed to prove to the criminal standard any of the three alleged breaches which raised issues of Russian and Jersey law. HHJ Pelling KC also ordered indemnity costs in relation to the contents of the affidavit evidence filed in support of the application.
E D & F Man Capital Markets Limited v Come Harvest Holdings Limited & ors [2022] EWHC 229 (Comm), [2022] EWCA Civ 1704: Acted (led by Huw Davies KC) for the successful claimant in Commercial Court and Court of Appeal proceedings arising out of a
£300 million fraud involving the provision of forged warehouse receipts in a “repo” transaction for the sale and repurchase of nickel. The case was heard by the Commercial Court over five weeks in 2021 and the Court of Appeal in December 2022.
Invest Bank PSC v El-Husseini & Ors [2022] EWHC 3008 (Comm): Acted (led by Louise Hutton KC) for the second defendant in respect of claims under s.423 Insolvency Act 1986 and various interim applications including security for costs.
Republic of Mozambique v Credit Suisse & Ors: Acted for the Ninth Third Party in Commercial Court proceedings in respect of a purported sovereign guarantee allegedly procured by bribery. Appeared as sole counsel at a CMC ([2023] EWHC 1148 (Comm)). Acted (led by Paul Key KC) for a successful applicant in a s 25 Civil Jurisdiction and Judgments Act 1982 application for a freezing order in support of Cypriot conspiracy proceedings.
ID v LU [2021] EWHC 1851 (Comm): Acted (led by Huw Davies KC) for a Ukrainian oligarch in a high-value claim involving claims for procuring breach of contract and anticipatory breach of contract.
Acted for a claimant bringing claims of conspiracy and vicarious liability against an employer in respect of employees’ involvement in a conspiracy.
Acted for several defendants in resisting a worldwide US$500m freezing injunction in the context of a US$580m fraud claim alleging that a Ukrainian bank was procured to enter into a series of sham transactions.
Advised (as sole counsel) on a potential civil fraud claim for £100,000 against an accountant and financial adviser which raises a number of complex issues of misrepresentation and unjust enrichment, as well as advising on potential interim relief including Norwich Pharmacal relief.
Advised (as sole counsel) on the prospects of commencing committal proceedings for knowingly making a false statement in a witness statement or affidavit, in circumstances where the potential defendant is resident outside the jurisdiction.
Advised (as sole counsel) on the merits of a potential claim for malicious prosecution.

Commercial chancery disputes

Many of Katherine’s cases involve trusts law, including E D & F Man Capital Markets Limited v Come Harvest Holdings Limited & ors [2022] EWHC 229 (Comm) (led by Huw Davies KC for the successful claimant) in which Calver J granted the claimant declarations that traceable proceeds were held on constructive trust.

Katherine also acted for the second defendant in Investbank PSC v El- Husseini & Ors, defending a s.423 claim, and is also currently assisting a company with an application for delivery up of a client file.

She has also been instructed as sole counsel to advise on commercial chancery matters, including on the advantages and disadvantages of a dormant LLP being kept on the register at Companies House and the protection afforded to members by a business and asset purchase agreement where the business and assets of the LLP have been sold.

Commercial dispute resolution

Commercial dispute resolution, in litigation and arbitration, is a core part of Katherine’s practice. She acts in and advises on a wide range of disputes for clients from a variety of industries, including financial services, insurance, art, commodities, and telecommunications.

Katherine has been recognised as a “Rising Star” in Legal 500 for Commercial Litigation and described as “an excellent junior barrister – her skills are far beyond her years of call. Her case analysis and drafting skills are of the highest standard, and she is, quite rightly, very highly in demand.”

Katherine has experience as both sole and junior counsel across a wide range of international and domestic commercial cases, including disputes regarding contractual construction, tortious duties, issues of quantum, and heavy civil fraud claims. Recent examples include:

NMC Health Plc v EY: defending EY in one of The Lawyer’s Top 20 cases of 2025 concerning a claim for USD 2.5 billion by the holding company of a Gulf-based healthcare group, arising out of a fraud allegedly perpetrated by its majority shareholders and senior management.
E D & F Man Capital Markets Limited v Come Harvest Holdings Limited & ors [2022] EWHC 229 (Comm), [2022] EWCA Civ 1704: Acted as junior counsel (led by Huw Davies KC) for the successful claimant in Commercial Court and Court of Appeal proceedings arising out of a £300 million fraud involving the provision of forged warehouse receipts in a “repo” transaction. The case was heard by the Commercial Court over five weeks in 2021 and the Court of Appeal in December 2022.
Advised on the terms of a major telecommunications contract and their implementation. Acted (as sole counsel) in a claim in the Commercial Court for damages for breach of a netting agreement between two oil traders.
Acted (as sole counsel) in a dispute between a finance company and borrower involving allegations that the finance company failed to mitigate losses by using an auction process rather than a private sale. A one day trial took place in the County Court.
Acted (as sole counsel) in a two day trial in the County Court concerning issues relating to implied terms in agency contracts and unjust enrichment.

Katherine has also recently published an article on how the scope of the transferred loss principle has been clarified by English courts in the last four years, which is available here.

Competition Law

Katherine has a particular interest in competition law and in 2022 spent four months on secondment in Freshfields Bruckhaus Deringer’s antitrust litigation team during which time she advised on regulatory and competition law issues, as well as assisted with a judicial review of the CMA.

Conflict of laws & private international law

Katherine’s practice is international in nature and the majority of her cases involve issues of conflicts of law and/or the application of foreign law (including, most recently, the laws of Ukraine, Russia, South Africa, Malaysia, Jersey and the United States).

Katherine regularly advises both potential claimants and defendants on jurisdictional issues.

For example:

WWRT Ltd v Zhevago [2024] EWHC 122 (Comm): Acted (led by James Sheehan) for the successful defendant in challenging the court’s jurisdiction on the grounds that the claimant did not have a real prospect of showing it had acquired the rights to claim against the defendant under an assignment, there was no good arguable case that the defendant had committed substantial and efficacious acts in England, and England was not the appropriate forum as Ukraine had not ceased to be an available appropriate forum by reason of the war.
ID v LU [2021] EWHC 1851 (Comm): Acted (led by Huw Davies KC) for the claimant resisting a jurisdiction challenge concerning the necessary and proper party jurisdictional gateway in circumstances where the anchor defendant had voluntarily accepted service of the claim form.
Acted in a successful jurisdiction challenge in the context of a US$580m fraud claim.

Katherine also has experience of preparing letters of request to obtain evidence for civil proceedings, most recently in Libyan Navigator Co Ltd v Libya Insurance Company (The “BADR”).

Employment

Katherine has been instructed to advise and act in a number of employment disputes. For example:

Acted for the claimants in InHealth Pathology Limited v Dr Steven Fox which involves claims for breach of confidence and wrongful interference with confidential information.
Advised on possible claims of vicarious liability and agency against parent companies.

Energy & natural resources

Acted (as sole counsel) on a claim in the Commercial Court for damages for breach of a netting agreement between two oil traders.

Human rights & civil liberties

Katherine has a particular interest in human rights matters, both at the domestic and international level, and has advised clients on human rights claims in a variety of contexts and in respect of the European Convention on Humans Rights and Human Rights Act 1998, as well as the International Covenant on Civil and Political Rights. In appropriate cases, Katherine acts pro bono.

Injunctions

Acted (led by Paul Key KC) for a successful applicant in a s 25 Civil Jurisdiction and Judgments Act 1982 application for a freezing order in support of Cypriot conspiracy proceedings.
Acted for several defendants in resisting a worldwide US$500m freezing injunction in the context of a US$580m fraud claim alleging that a Ukrainian bank was procured to enter into a series of sham transactions.
Advised as sole counsel on the continuance of an anti-suit injunction and its terms.

Investment treaty disputes

International investment law and arbitration form a substantial part of Katherine’s practice. Katherine regularly on advises on issues arising out of investment treaties and has been involved in several arbitrations. Recent examples include:

A claim brought by a multi-sector investor in a State of the Caucasus region, under a bilateral investment treaty. The claim particularly raised issues relating to excise duties, national competition law, enforcement of revenue law, and the application of most favoured nation provisions. Led by Sam Wordsworth KC and Lucas Bastin KC.
A claim brought by an investor in Belize, under a bilateral investment treaty. The claim arose out of an infrastructure project and raised issues as to the application of the fair and equitable treatment standard and less favourable treatment provisions. Led by Angeline Walsh KC.
Advised on a potential denial of justice claim by an investor under a bilateral investment treaty.Advised on the scope of the police powers doctrine as an exception to the requirement of compensation for lawful expropriation.
Advised on potential investment treaty claims against a government and on the specific wording of the BIT in question which provided that an arbitration would only take place if the parties subsequently gave their consent.

Media, art, entertainment

Katherine has a particular interest in cases relating to media, art and entertainment. She has previously acted as sole counsel for a London art dealer in a payment dispute, as well as for a well-established auctioneer in respect of an unjust enrichment claim arising out of an agency relationship. She has also acted in an authenticity dispute.

Katherine also wrote a case note (available here) on the decision of Hickox v Dickinson [2020] EWHC 2520 (Ch), in which Ms Clare Ambrose sitting as a deputy High Court judge considered the art-world custom of not disclosing the names of private buyers of art works.

Katherine has also assisted with advising on media law issues, including potential claims arising from the publication of personal information in newspapers and the availability of injunctions for defamation and the publication of confidential information.

Professional negligence

Katherine has been instructed to advise and act in a number of high-profile professional negligence disputes. For example:

NMC Health Plc v EY: defending EY in one of The Lawyer’s Top 20 cases of 2025 concerning a claim for USD 2.5 billion by the holding company of a Gulf-based healthcare group, arising out of a fraud allegedly perpetrated by its majority shareholders and senior management.
Acted in a claim against insurance brokers for negligence when obtaining insurance.
Acted (as sole counsel) proceedings involving a claim for professional negligence on the part of paralegals, as well as claims for breaches of the Consumer Rights Act and the Consumer Protection from Unfair Trading Regulations.
Assisted RPC’s regulatory team while on an eight month secondment in 2020/21 with a major FRC.

Public & administrative law

Katherine has considerable experience advising in respect of domestic public and administrative law matters. In 2022 Katherine was seconded for four months in Freshfields Bruckhaus Deringer’s antitrust litigation team during which time she assisted with multiple judicial reviews and administrative law proceedings. More recently she has advised multiple clients on possible grounds for judicial review applications. In appropriate cases, Katherine also acts pro bono.

Public international law

Katherine has been instructed to advise and act in a number of cases involving issues of public international law. She has particular experience in respect of immunities, human rights, sanctions, treaty interpretation, and anti-corruption mechanisms, as well as a substantial practice in international investment law and arbitration. Recent examples of Katherine’s work in this field include:

Acted as junior counsel in a claim brought by a multi-sector investor in a State of the Caucasus region, under a bilateral investment treaty. The claim is for breaches of protections for fair and equitable treatment, full protection and security, an ‘umbrella clause’, and prohibitions on unlawful expropriation and discrimination. Led by Sam Wordsworth KC and Lucas Bastin KC.
Advised on the mechanisms for asset recovery under international instruments (including the UN Convention Against Corruption, the African Union Convention on Preventing and Combatting Corruption and the UN Convention Against Transnational Organised Crime), regional instruments (such as the Conventions of the Organisation of American States, the Council of Europe, and the 2014/42/EU Directive), as well as domestic asset recovery legislation in a diverse range of jurisdictions.
Advised on the scope of the police powers doctrine as an exception to the requirement of compensation for lawful expropriation.
Advising on immunities issues before the English courts in the context of potential enforcement proceedings against a State’s assets in the jurisdiction.
Advising on immunities issues in the context of freezing injunctions and third party debt .
Advising on sanctions-related issues, including the impact of Regulation 2022/328 and Regulation 2022/428 on loan agreements.

Unjust enrichment & restitution claims

Many of Katherine’s cases involve claims arising out of unjust enrichment, which is an area of English law in which Katherine has a particular interest having studied restitution on the BCL. Katherine is currently advising as sole counsel on a potential civil fraud claim which raises issues of failure of consideration and undue influence and also recently assisted with research for a claim relating to mistaken forbearance and set off. During pupillage, Katherine worked on a number of unjust enrichment cases including claims arising from a breach of privacy and in relation to a proprietary claim for the return of Bitcoin.

Career

2020: Tenant at Essex Court Chambers

2019-2020: Pupillage at Essex Court Chambers

2019: Called to the Bar (Gray’s Inn)

2018-2019: Guest Teacher in Law at the London School of Economics

Education

2019: BPTC, City University, Outstanding

2018: BCL, Merton College, Oxford (studied conflict of laws, restitution, commercial remedies and corporate insolvency)

2017: BA Law (Jurisprudence), Merton College, Oxford, First Class

Awards

2018: Bedingfield Scholarship, Gray’s Inn

Third in the OEC Times Law Awards 2018