Overview
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.
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.
Results
- Represent Apache Corporation, a publicly traded oil and gas exploration and production company, in the Tax Court in tax disputes involving carrybacks of specified liability losses and research and development credits (Apache Corporation v. Commissioner)
- Represents Trail King Industries, a leading manufacturer of trailers, in the US District Court for the District of South Dakota in tax disputes involving a refund of federal excise taxes on heavy trucks and trailers (Trail King Industries, Inc. v. United States)
- Represents Apache Corporation, a publicly traded oil and gas exploration and production company, in the US District Court for the Southern District of Texas in tax disputes involving refunds related to a capital loss carryback and research and development credits (Apache Corporation v. United States)
- Represents a publicly traded waste collection company before the IRS Independent Office of Appeals and in preparation for litigation related to the federal motor fuels excise tax
- Represented US Venture, a large fuel distribution company, in the District Court for the Eastern District of Wisconsin involving the federal alternative fuel mixture credit (US Venture v. United States)*
- Represented EOG Resources, Inc., a publicly traded oil and gas exploration and production company, in the Tax Court for a tax dispute involving the alternative minimum tax resulting from the company’s hedging program (EOG Resources, Inc. v. Commissioner)*
- Represented a publicly traded multinational oil and gas exploration and production company in the Tax Court in a case involving foreign tax credits and deductions*
- Represented a publicly traded building products company in the Tax Court in a case involving a contingent liability management company transaction*
- Advised a multinational consumer products company on the tax consequences of an intellectual property transfer and a repatriation of foreign earnings*
- Advised a publicly traded refinery on a substantial intercompany loan and whether the loan qualified as debt for federal income tax purposes*
- Advised a substantial foreign-based airline on the federal excise taxes applicable to air transportation services*
- Represented a major integrated energy company in the Court of Federal Claims in relation to the company’s tax credit eligibility for the production of crude oil from tar sands*
- Represented a major integrated energy company in the District Court for the Southern District of Texas in a case centered around a structured transaction*
- Represented a major publicly traded pharmaceutical company in the District Court for the District of New Jersey in relation to discovery matters involving a repatriation of earnings to the United States*
- Advised on transfer pricing and drafted intercompany service agreements for a joint venture of two publicly traded oilfield service companies for purposes of the joint venture’s global transfer pricing plan*
*Matter handled prior to joining McDermott.
Recognitions
- Chambers USA, Tax: Litigation – Texas, 2015–2024
- Chambers USA, Band 2 in Tax: Litigation – Texas, 2024
- Legal 500 US, Recommended, 2024
- Best Lawyers in America, Tax Law and Litigation and Controversy – Tax, Chicago, 2023–2025
- International Tax Review, 2013–2023, Tax Controversy Leader
Community
- Internal Revenue Service Advisory Council (IRSAC), past chair of the Large Business & International subcommittee, 2016–2018
- State Bar of Texas Tax Section, past chair of the Energy and Natural Resources Committee, 2011–2013
Credentials
Education
New York University School of Law, LLM, 1998
Loyola Law School, JD, 1997
Millsaps College, BBA, 1993
Courts/Agencies
US District Court for the Southern District of Texas
US Court of Federal Claims
US Tax Court
Admissions
Texas
Louisiana
