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Theodore J. Angelis

Theo Angelis is an intellectual property and appellate litigator who appears in trial and appellate courts, in administrative tribunals, and in arbitration proceedings throughout the United States. 

Theo’s unique experience—as an intellectual property litigator who co-chaired the firm’s appellate practice and has an active appellate practice—allows him to craft and present especially persuasive and compelling arguments. He also provides clear and strategic advice to clients facing unsettled or complex legal issues, and he assists them in efficiently solving problems and minimizing risk.

Theo has litigated patent and other IP matters before the U.S. District Courts in California, Delaware, Illinois, Louisiana, Minnesota, New York, Oregon, Nevada, New Jersey, Pennsylvania, Texas, and Washington, as well as the Patent Trial and Appeal Board and International Trade Commission.  Theo's appellate practice focuses primarily on the Federal and Ninth Circuits, as well as the D.C. Circuit, where Theo served as a law clerk. Theo also regularly handles appeals in state appellate courts. 

Theo has received numerous awards and honors.  He is listed in the Best Lawyers in America and as a Washington Super Lawyer, and he recently was recognized by the King County Bar Association as Mentor of the Year.  Earlier in his career, the King County Bar Association named him Outstanding Young Lawyer.  Theo served as the editor of the Washington Lawyer’s Practice Manual for many years, and while in law school served as articles editor for the Yale Law Journal and managing editor of the Yale Law & Policy Review

Theo is a frequent speaker and presenter on strategic litigation issues, not only related to patent and IP litigation but also legal ethics, privacy for electronic communications, internal investigations, developments in Internet law, and effective litigation strategies. 

  • Clerkship, Hon. Stephen F. Williams, U.S. Court of Appeals for the District of Columbia Circuit, 1999-2000
  • Listed in The Best Lawyers in America©, 2013- 2021
  • Listed in Washington Super Lawyers (2014–2018)
  • Citizen of the Year (2016) by St. Demetrios Greek Orthodox Church
  • King County Bar Association Mentor of the Year (2012)
  • King County Bar Association’s Outstanding Young Lawyer (2006)
  • Recipient of NWIRP Amicus Award (2011) (awarded to Castillo litigation team)
  • Selected to the Washington Rising Stars List (2004-2009, 2011, 2012)
  • Co-Chair, IP Litigation Committee of the Federal Bar Association of the Western District of Washington.
  • Chair, King County Bar Association Fair Campaign Practices Committee
  • Member, King County Bar Association’s Leadership Committee
  • Member, Attorney General’s Task Force on Unaccompanied Children
  • Leadership Tomorrow, Class of 2008
Additional Thought Leadership Pages
  • Internet and Technology Law – Practical Guidance for the Washington Practitioner (2012)
  • Indian Law, in Washington Lawyers Practice Manual (2012)
  • Rule 11, (with Ramona Emerson) in Washington Civil Procedure Deskbook (2007).
  • “Investing Public Money in Private Markets: What are the Right Questions?,” Framing The Social Security Debate: Values, Economics, & Politics (Douglas Arnold, Michael Graetz, & Alicia Munnel, eds., 1999).
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