Daniel Isenberg

Daniel accepts instructions (both led and unled) in all areas of commercial dispute resolution and business protection matters. He has particular experience in claims relating to breach of directors’/fiduciary duties and boardroom disputes.

Current and recent instructions include:

• Stobart Group Ltd v Tinkler [2019] EWHC 258 (Comm), concerning an executive director’s breach of his fiduciary and contractual duties.
• Abramovich v Hoffmann (ChD), a high-profile claim for breaches of fiduciary and contractual duties, and for restitution of tax liability paid to HMRC.
• Acting in a breach of directors’ duties, conspiracy and restitution claim brought by a public company against both a former director and one of its shareholders.
• Acting as sole counsel for a former CEO in contractual claims against a publicly-listed company.
• Acting for an individual defendant in multi-party conspiracy and breach of duty claim brought by a publicly-listed company.
• Idris-Goudarz v Goudarz [2020] EWHC 1878 (Ch): acting as sole counsel in a multi-day Chancery Division trial for the applicant, successfully enforcing a Tomlin Order and resisting her father’s debt claim under purported oral agreements.
• Advising a solicitor in relation to a contentious exit from a firm, including in relation to the scope and applicability of various covenants.
• Arbitration proceedings in a team move case for an international law firm.

Daniel’s practice frequently involves cases engaging fraud and allegations of dishonesty.  Current and recent instructions include:

• Tinkler v Esken [2022] EWHC 1375 (Ch), successfully defending a claim to set aside a High Court judgment for fraud (including before the Court of Appeal [2023] Ch 451).
• Advising a company in respect of forged energy contracts purportedly taken out in its name.
• Advising a company in relation to a ‘business email compromise’ incident (email fraud) which led to payments owing to it instead being made to third-party fraudsters.
• Acting for a shareholder in fraudulent misrepresentation claims concerning investments made in the energy and mining sector.
• Acting for multiple defendants in deceit, conspiracy and inducement of breach of contract claims for over €1.4 billion concerning trades in medium term notes.

In addition to the business protection matters above, Daniel has built up experience on a range of statutory and common law employment matters, including claims under the Equality Act, unfair dismissal, minimum wage, working time and redundancy-related claims. He regularly appears as sole counsel before the Employment Tribunal, including in multi-day trials.

Daniel is particularly well-placed to advise and frequently acts on matters relating to employee- shareholders and employee-directors, and the overlap between employment and company law, including boardroom disputes and breaches of directors’ and/or fiduciary duties.

Recent instructions include:

• As sole counsel, successfully defending a leading university and individual academics in claims of race-related harassment, discrimination and victimisation following a six-day trial.
• Ferguson v Astrea Asset Management Ltd [2020] ICR 1517; [2020] IRLR 577: concerning whether variations to employment contracts beneficial to the employees were rendered void by the TUPE Regulations.
• Hall v London Lions Basketball Club (UK) Ltd [2021] IRLR 17, acting as sole counsel before the EAT on behalf of a professional basketball player on an appeal concerning the measure of wrongful dismissal damages in a fixed-term contract.
• Maccaba v Waratek, complex High Court litigation relating to allegations of wrongful dismissal and breach of contract and counter-allegations of breach of contractual and fiduciary obligations in relation to the former chief executive of the anti-virus technology company.
• Arbitration proceedings in a team move case for an international law firm.

Daniel has developed particular expertise in state immunity matters before the Employment Tribunal, instructed as sole counsel on behalf of foreign states.

As a judicial assistant, Daniel drafted submissions to the Privy Council in place of the absent Respondent in University of Technology, Jamaica v Industrial Disputes Tribunal [2017] UKPC 22 (see para 2), about whether the Industrial Disputes Tribunal was entitled to take into account matters of which the employer was unaware at the time of the dismissal.

Daniel is particularly well-grounded in equality and discrimination law following his involvement in Essop v Home Office, Naeem v Secretary of State for Justice [2017] UKSC 27, concerning whether in an indirect discrimination claim there is a need to establish why a provision, criterion or practice causes individuals with a protected characteristic particular disadvantage (as a judicial assistant). He is also a member of the EHRC’s B Panel of Counsel.

Daniel recently appeared in the Supreme Court in the leading case on the approach under the European Union (Withdrawal) Act 2018 to claims where the underlying cause of action accrued prior to Brexit: Lipton v BA Cityflyer Ltd [2024] UKSC 24.

He is also a member of the Attorney General’s C Panel of Treasury Counsel. He acted for the successful defendants in R (EU Lotto Ltd and others) v Secretary of State for Digital, Culture, Media and Sport [2019] 1 CMLR 41, an EU law challenge to the ban on betting on non-UK Euromillions lotteries; and R (MP) v Secretary of State for Health and Social Care [2018] EWHC [3392] (Admin), consultation- and PSED-based challenges to reforms to the regime for charging ‘overseas visitors’ for NHS services.

Recent instructions include:

• R (the3Million Limited & ors) v Minister for the Cabinet Office [2021 EWHC 245 (Admin)], acting for the Defendant in the judicial review brought by a campaign group into the widely-publicised problems associated with the May 2019 European Parliamentary elections and associated damages claim.
• Brook House Public Inquiry – acting for a core participant in the Article 3 public inquiry into allegations of abuse and mistreatment at the Brook House immigration removal centre, following an undercover BBC Panorama report.
• Advising and acting for central government departments in relation to their responses to the COVID-19 pandemic, including in relation to the guidance on visits to residential care homes (the John’s Campaign Judicial Review).

With his background at the Ministry of Defence, Daniel has particular experience and expertise in defence and national security matters. He was the Deputy Executive Editor (Print) of the Harvard National Security Journal and has acted as a researcher for the then-Independent Reviewer of Terrorism Legislation, David Anderson KC.  In the national security field, Daniel acted for the Government in Bank Mellat v HM Treasury concerning the bank’s original damages claim, as well as its challenge to subsequent sanctions orders.  He also acted for the successful defendant in R (Schofield) v Secretary of State for the Home Department [2021] EWHC 902 (Admin), a challenge under Article 2 to the UK’s ban on the admissibility of ‘intercept evidence’, arising out of the high-profile collapse of the prosecution of the Chief Constable of Greater Manchester Police, following the findings public inquiry into the shooting of Anthony Grainger. He has been involved in Belhaj v Straw [2017] UKSC 3, regarding the application of the ‘foreign act of state’ doctrine (as a judicial assistant). Daniel has also advised clients on matters concerning RIPA and online monitoring, as well as the National Security and Investment Act 2021.  He also acts before the Employment Tribunal in national security proceedings under Rule 93.

During his time as a judicial assistant, Daniel worked on the leading constitutional cases before the Supreme Court, including R (Miller) v Secretary of State for Exiting the European Union [2017] UKSC 5, regarding the Government’s ability to notify the EU of the UK’s withdrawal under Article 50 TFEU without Parliamentary approval.

Daniel is experienced in a wide range of complex issues of public international law, with a particular expertise and interest in questions of immunities and privileges (especially under the VCDR). He is regularly instructed as sole counsel on behalf of foreign states in relation to issues of state immunity.

He has been involved in a number of the leading recent cases on questions of immunity, including:

•  Reyes v Al-Malki [2017] UKSC 61, concerning the application of the ‘commercial activity’ exception under Article 31(1)(c) of the VCDR to allegations of trafficking (as a judicial assistant).
•  R (Bancoult No. 3) v Secretary of State for Foreign and Commonwealth Affairs [2018] UKSC 3, about the admissibility of a ‘Wikileaks’ cable under the VCDR (as a judicial assistant).
•  Benkharbouche v Secretary of State for Foreign and Commonwealth Affairs [2017] UKSC 62, regarding the compatibility of provisions of the State Immunity Act 1978 with the ECHR and EU Charter, and their basis in customary international law (as a judicial assistant).

Daniel has worked on further PIL matters, including Al-Waheed v Ministry of Defence [2017] UKSC 2 on the power under international law to detain in a non-international armed conflict (as a judicial assistant); as well as during his time as a ‘Foreign Law Clerk’ at the Supreme Court of Israel.

He has also been instructed in proceedings before the Supreme Court of the British Indian Ocean Territory (Diego Garcia).

Daniel also has a significant data protection practice, focusing in particular on ‘data breach’ claims, involving the compromise of the personal data of a large number of data subjects, whether inadvertent or by cyber-criminals.

He acted for the defendant in the British Airways Group Litigation arising out of the cyber-attack on BA’s systems in autumn 2018 – the first mass piece of group litigation under the GDPR. He is also acting in a number of other data breach claims, each with potentially significant numbers of claimants.

In addition to a number of ongoing large-scale data breach instructions, Daniel’s current and recent cases in this field also include:

•  FKJ v RVT, a misuse of private information claim concerning allegations of unlawful access to a junior employee’s WhatsApp account and counterclaims of malicious prosecution
•  RTM v Bonne Terre Ltd & Hestview Ltd [2025] EWHC 111 (KB), regarding the lawfulness of data processing, in particular concerning marketing and profiling, by a betting and gambling company in relation to a customer who considered himself to have a gambling addiction.

Daniel also regularly acts for the Information Commissioner and public authorities in FOIA appeals.