Ronnie Barnes

Vice President


  • London


Ronnie Barnes coheads Cornerstone Research’s international arbitration and litigation practice. Dr. Barnes is an expert in accounting, damages, and valuation. He specializes in cases that raise complex valuation issues, including the estimation of the cost of capital, the determination of country risk premia, and the valuation of complex financial instruments such as derivatives and structured finance products. Who’s Who Legal has recognized Dr. Barnes as a leading expert witness in legal arbitration and a Global Leader in assessing the quantum of damages in the financial advisory and valuation field.

Dr. Barnes has provided written and oral testimony in a number of litigation and arbitration matters in the United Kingdom, United States, Canada, South Africa, and internationally. He has addressed such topics as the tax treatment of hire purchase contracts; the quantum of damages in commercial disputes; the economic equivalence of different financial derivatives; the cost of capital in the contexts of a competition enquiry and valuation disputes; the use of derivatives in alleged share price manipulation; and stock market efficiency in shareholder actions.

In addition to serving as a testifying expert, Dr. Barnes leads teams that support academic and practitioner experts. In this capacity, he has worked on numerous matters related to financial institutions and financial products. He has addressed issues related to the analysis of damages stemming from alleged misrepresentations and omissions in corporate disclosures, as well as other matters requiring sophisticated accounting, financial, and/or economic analysis.

Dr. Barnes has published research on a range of topics, notably cross-border valuation, valuation methodologies, damages, and the role of economic and econometric analyses in damages assessments. He has authored or coauthored multiple articles, as well as chapters in leading reference books on international arbitration.

A UK-qualified chartered accountant, Dr. Barnes previously held positions in accounting and investment banking firms, as well as a consulting firm and academia. He has more than a decade of experience teaching courses in corporate finance, accounting, and valuation, among other topics.

Press Release

WWL: Arbitration Expert Witnesses 2023

Press Release

WWL Consulting Experts: Financial Advisory and Valuation – Quantum of Damages 2022


The Role of Economic Analysis in UK Shareholder Actions

Press Release

WWL: Arbitration Expert Witnesses 2022

Press Release

Cornerstone Research Promotes Seven to Vice President

Press Release

2021 Who’s Who Legal: Consulting Experts


Market Abuse 2021: Key Takeaways


Expert Forum: Market Abuse 2021

  • “Shareholder Litigation,” New York State Bar Association 2022 London Global Conference, 30 November 2022
  • “Selected Topics on Damages,” GAR Live: New York, 2022, 30 September 2022
  • GAR Live: Atlanta 2022, 13 September 2022
  • GAR Live: Damages 2022, 15 March 2022
  • “European Shareholder Group Actions—The Role of Economic Analysis,” Dispute Resolution Forum 2021, 16 June 2021
  • Expert Forum: Market Abuse 2021, Cornerstone Research, 25 February 2021
  • “What Users and Their Counsel and Experts Want from Arbitrators,” GAR Interactive: Damages, 4 February 2021
  • “Remedies and Defences in COVID-19-related Arbitration,” Dublin International Arbitration Day 2020, 20 November 2020
  • Expert Forum: European Shareholder Group Actions—The Role of Economic Analysis, Cornerstone Research, 19 November 2020
  • “Latest Trends and Developments in Emerging Markets,” 7th Annual GAR Live Paris, 27 November 2019
  • “Economic Issues in International Arbitration: A Primer,” 14th Annual Conference on International Arbitration and Mediation, 22 November 2019
  • “The Role of Counsel in the Quantum Phases of International Arbitration,” 8th Annual Damages in International Arbitration, 19 November 2019
  • “Three Topical Challenges Related to the Calculation of Damages,” GAR Live Advanced Damages Workshop 2019, 7 November 2019