Diann Smith - McDermott Will & Emery


Diann Smith focuses her practice on state and local taxation and unclaimed property advocacy. Diann advises clients at any stage of an issue, including planning, compliance, controversy, financial statement issues and legislative activity. Her goal is to find the most effective method to achieve a client’s objective regardless of when or how an issue arises. Diann emphasizes the importance of defining a client’s objective – whether it is finality of a frequently audited issue, quick resolution of a stand-alone tax liability, or avoiding competitive disadvantages in the application of a tax. The defined objective then governs the choice of the path to a solution.

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  • On behalf of Microsoft, won a pivotal case in the District of Columbia challenging the jurisdiction’s transfer pricing audit methodology
  • On behalf of a Firm client, obtained a complete settlement concession from the District of Columbia resulting in zero additional tax due on transfer pricing audit

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  • The Legal 500
  • Unclaimed Property Professionals Organization (UPPO)
    • Shining Star Award, 2021 and 2022
    • Award of Merit, 2017


  • Council on State Taxation Practitioner Connection
  • Volunteer at the DC Bar Landlord Tenant Resource Center
  • Unclaimed Property Professionals Organization, co-chair of the Government Relations Advocacy Committee
  • Serves as co-chair of the UPPO Government Relations and Advocacy Committee


Georgetown University Law Center, JD, 1991
Miami University, BA, 1985

District of Columbia
New York

Courts / Agencies
US Court of Appeals for the Sixth Circuit
US District Court for the District of Ohio