Penelope Warne

Joel D. Harrison is a top attorney recognized by Best Lawyers in the practice area(s) of Information Technology Law and Outsourcing. Joel D., who practices law in London, United Kingdom, has been recognized since 2022. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Joel D. is held by other top lawyers in the same geographic and legal practice area.

Penny Madden is an English qualified Queen’s Counsel and serves as Co-Partner-in-Charge of the London office at Gibson, Dunn & Crutcher. She is Co-Chair of the International Arbitration Practice Group and a member of the firm’s Transnational Litigation Practice Group. She has a wide range of experience in all key aspects of international arbitration with particular expertise in shareholder, telecommunications, SPA, energy, international trade and insurance disputes. She repres...

Cy Benson is a U.S. and English qualified partner in the London office of Gibson, Dunn & Crutcher and serves as Co-Chair of the firm’s International Arbitration Practice Group. Mr Benson represents clients from a wide variety of sectors before commercial and investment treaty tribunals with particular experience in telecoms, oil & gas, mining and infrastructure disputes. He continues to represent a Dutch and a Luxembourg investor in two separate multi-billion dollar arbitration ...

Christopher Haynes is a top attorney recognized by Best Lawyers in the practice area(s) of Capital Markets Law. Christopher, who practices law in London, United Kingdom, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Christopher is held by other top lawyers in the same geographic and legal practice area.

John McElroy is a top attorney recognized by Best Lawyers in the practice area(s) of International Arbitration. John, who practices law in London, United Kingdom, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which John is held by other top lawyers in the same geographic and legal practice area.

Simon Airey focuses his practice on global, cross-border and internal investigations, financial and regulatory crime, bribery and corruption, money laundering, tax and fraud inquiries, data breaches, dawn raids, asset tracing, international enforcement and corporate compliance issues. He has conducted a wide range of investigations and corporate defence assignments in different sectors, including construction, defence, financial services, gambling, oil and gas, logistics, pharmaceuticals and ...

Elisabeth I. Baltay is a top attorney recognized by Best Lawyers in the practice area(s) of Insolvency and Restructuring Law. Elisabeth I., who practices law in London, United Kingdom, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Elisabeth I. is held by other top lawyers in the same geographic and legal practice area.

Graham Defries is a top attorney recognized by Best Lawyers in the practice area(s) of Life Sciences Law. Graham, who practices law in London, United Kingdom, has been recognized since 2024. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Graham is held by other top lawyers in the same geographic and legal practice area.

Sebastian FitzGerald is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law. Sebastian, who practices law in London, United Kingdom, has been recognized since 2024. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Sebastian is held by other top lawyers in the same geographic and legal practice area.

Rob Day is a partner in Proskauer’s Corporate Department and a member of our Private Equity Transactions, Mergers & Acquisitions and Sports Groups. Rob’s practice focuses on public and private M&A, leveraged buyouts and joint ventures, private equity and portfolio company transactions. His clients include global corporations, asset managers and private equity houses, advising on their strategically important transactions across financial services, consumer, sports, media a...