Brendan Sponheimer

Brendan J. Sponheimer

Baker & McKenzie LLP


Brendan Sponheimer is a partner in the New York office of Baker McKenzie and a member of the Tax Practice Group. Prior to joining the Firm, Brendan was a Tax Controversy and Transfer Pricing Associate in New York, and an Attorney Advisor for Judge Joseph Robert Goeke of the United States Tax Court in Washington, D.C.

Practice Focus

Brendan focuses his practice on tax disputes and transfer pricing matters. He represents taxpayers at all levels of federal tax controversy, including IRS audits, administrative appeals, competent authority, and litigation before the United States Tax Court and United States Court of Federal Claims. His experience includes controversies with economic substance, substance-over-form, and transfer pricing issues.

Professional Associations and Memberships

  • American Bar Association, Tax Section


  • New York~United States (2012)
  • Connecticut~United States (2011)


  • Georgetown University Law Center (LLM, with distinction, Dean's List) (2011)
  • Western New England University School of Law (JD, cum laude) (2010)
  • Yale University (BA) (2007)


  • English


  • Author, "United States: Will the Supreme Court finally deflate the IRS's overblown AIA argument?," Baker McKenzie InsightPlus, 11 September 2020

  • Co-author, “Transformation of ‘Initial Determination’ to ‘Definite Decision’ in Penalty Approval Case,” Baker McKenzie Tax News and Developments, February 2020

  • Co-author, “Tax Reform's Impact on the Transfer Pricing Examination Process for Inbound Companies,” 31 Journal of International Taxation 38, January 2020

  • Co-author, “U.S. Transfer Pricing Examinations under the Transfer Pricing Examination Process,” 30 Journal of International Taxation 44, April 2019

  • Co-author, “Attorney-Client Privilege Claim Upheld in IRS Examination of Captive Insurance Company,” BNA Daily Tax Report, 12 April 2017

  • Co-author, “Looking for Clues in the IRS’s Campaign Announcement” BNA Daily Tax Report, 24 March 2017