Theo Angelis is a first-chair International Trade Commission and District Court litigator, and he also serves as one of the leaders of the IP Litigation Group at K&L Gates.
Theo has extensive experience representing clients in Greater China, throughout Asia, and in the United States. Theo served as lead ITC counsel for Sharp Corporation in the 1201 Investigation and serves as lead ITC counsel for Realtek Semiconductor Corp. in the 1222 Investigation. He also was lead invalidity counsel at trial for Amperex Technology Ltd. in the 1087 Investigation, and he has held other leading roles in numerous ITC investigations throughout his career.
In addition, Theo litigates in District Courts throughout the United States, for both Asian and U.S. companies. He is lead counsel for ZTE, and recently served as lead counsel for Quanta, Advantech, and ADLINK Technology, in multiple cases for each. Theo also has served as lead counsel, in several matters each, for innovative U.S. technology companies, including Square, Amazon, and Expedia.
Theo also represents clients such as Sharp Corporation in appellate matters. Theo’s unique experience—as an intellectual property litigator who previously led 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'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.
- Clerkship, Hon. Stephen F. Williams, U.S. Court of Appeals for the District of Columbia Circuit, 1999-2000
- Listed in Chambers USA for Intellectual Property in Washington, 2021
- Listed in The Best Lawyers in America©, 2013- 2021
- Listed in Washington Super Lawyers (2014–2021)
- 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
- 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).