Toby Grimstone

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...

Trevor has over 30 years of experience in providing corporate and international tax advice. His practice focuses on advising client on the tax planning aspects of international transactions and strategic tax planning for global clients. He has particular experience in advising clients in the technology sector and IP-rich companies.Trevor has also advised clients on the design and implementation of global private equity and investment funds, including advising executive teams on the structurin...

Geoffrey L. Wynne is head of the Trade and Commodities Finance Group and has extensive experience in banking and finance, specifically corporate and international finance, bank mergers, acquisitions, conversions and restructurings, trade and structured trade and commodity finance, structured finance, asset and project finance, syndicated lending, equipment leasing, workouts and financing restructuring, leveraged and management buy-outs and general commercial matters. Geoff is one of the leadi...

Stephen A. Thierbach is a US-qualified corporate partner in the London office of Gibson, Dunn & Crutcher. A senior U.S. securities lawyer, he advises issuers, underwriters and selling shareholders on complex, innovative and multi-jurisdictional offerings of equity, equity-related and debt securities. He has a broad capital markets transactions practice, with a focus on initial public offerings and secondary offerings, and has represented corporates, investment banks, private equity firms ...

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 ...

James Cox is a partner in the London office of Gibson, Dunn & Crutcher and a member of the firm’s Labour and Employment Practice Group. Mr. Cox has extensive experience in contentious and non-contentious labor and employment matters, with an emphasis on cross-border employment issues, collective labor and industrial disputes, redundancies and workforce restructurings, ARD/TUPE, the employment aspects of public and private mergers and acquisitions and outsourcing arrangements, corpor...

Gillian Sproul is a lawyer recognized by Best Lawyers in the practice area of Competition Law. Gillian practices law in London, United Kingdom Best Lawyers has recognized Gillian Sproul since 2025. The Best Lawyers recognition is based on a peer-review survey of lawyers in the same geographic region and legal practice area. The recognition reflects the professional regard in which Gillian Sproul is held by other lawyers.

Aymen Mahmoud is the co-head of the London Finance, Restructuring and Special Situations Group. He focuses his practice on complex debt financing transactions for private equity funds and their portfolio companies, hedge funds, corporate borrowers and issuers and other financial institutions including banks, direct lenders, family offices and other alternative sophisticated capital. His experience includes acting in respect of direct lending, leveraged buyouts, domestic and cross-border syndi...

Robert Haak is a lawyer recognized by Best Lawyers in the practice area of High Yield Products. Robert practices law in London, United Kingdom Best Lawyers has recognized Robert Haak since 2024. The Best Lawyers recognition is based on a peer-review survey of lawyers in the same geographic region and legal practice area. The recognition reflects the professional regard in which Robert Haak is held by other lawyers.

Charlie Caher is a partner in the Firm's Litigation/Controversy Department, and a member of the International Arbitration Practice Group. He joined the Firm in 2008. Mr. Caher is based in the London office, where he practices International Arbitration and English High Court Litigation.