Smarter Controversy: What Tax Directors Wish They Knew Before Entering a UK Tax Dispute

Advises clients on federal tax controversy matters and tax litigation across the technology, healthcare, and pharmaceutical sectors

Represents high-net-worth individuals and complex partnerships

Handles all stages of federal tax controversies, including audits, administrative appeals, alternative dispute resolution, and litigation

Counsels clients on domestic and international tax issues, including transfer pricing, research credits, Subpart F, and foreign tax credits

David Jamieson has over 20 years’ experience advising on VAT, indirect taxes and contentious tax matters. He is dual-qualified as a Solicitor Advocate and a Chartered Tax Adviser, offering clients a combination of litigation experience and deep technical tax knowledge.

David has significant experience in advising on complex VAT matters, handling tax audits and enquiries, tax risk management, tax dispute resolution and public law. His practice covers the entire lifecycle of a tax issue, focusing on both proactive, non-contentious advisory work to prevent disputes, and robust defence strategies when challenges arise. David has extensive experience at all stages of the appeal process.

David’s practice is focused on the financial services, technology, media and life science sectors. Before taking up his current role, he spent 14 years in the London office of a US-based multinational law firm, having previously worked at a Big Four firm and a leading UK-based law firm.

Shawn O’Brien is nationally recognized by his peers and clients as a leading tax practitioner with a focus on tax litigation and controversies involving state, federal and international tax authorities. Drawing on his 25 years of experience, Shawn represents clients in tax examinations and administrative appeals and, when necessary, serves as a forceful advocate in litigation before the US Tax Court, US district courts, the US Court of Federal Claims, state courts and federal appellate courts. Shawn is the managing partner for the firm’s Houston office.

Clients interviewed in the Chambers USA Legal Guide 2024 shared that Shawn is “a trusted adviser and his level of service is superb” and he “has been a good strategic tax partner for our company,” particularly noting his “in-depth knowledge of our industry.”

Shawn’s experience spans a broad range of tax issues that affect many different industries, including energy, renewables, financial services, life sciences, manufacturing, media and entertainment, technology and aviation. He advises domestic, foreign and multinational corporations, partnerships, master limited partnerships, real estate investment trusts and limited liability companies on tax issues in connection with foreign and domestic transactions.

He also counsels clients in disputes involving transfer pricing, debt versus equity, loss carrybacks, international withholdings, advance pricing agreements, tax shelter disallowances, research and development tax credits, changes in accounting methods, captive insurance, related-party transactions, repatriation structures, inbound distributors, foreign credit transactions and penalty abatements. Shawn has also developed a market-leading federal and state excise tax practice that advises some of the largest corporations on excise tax planning and controversies.