Patrick W. Pearsall
Partner
Washington, D.C.

Patrick W. Pearsall
Partner
Washington, D.C.
Contact Details
Patrick has extensive experience representing parties in international disputes and providing strategic advice on asset protection, global investment and commercial contracts. He served in the U.S. State Department for nearly a decade, working on economic and natural resource diplomacy, and departed as the Chief of Investment Arbitration.
Patrick has successfully resolved claims involving billions of dollars. He is often called upon to provide strategic counsel to parties when they face international disputes, including matters related to energy and natural resources, and has experience with nearly all of the major international commercial arbitration rules. He is a trusted adviser to Fortune 500 companies and governments alike.
In addition to his representations, Patrick was on a drafting committee for revision of the International Court of Arbitration’s (ICC) rules and led the negotiations of several bilateral and multilateral treaties. He advised on the negotiation of the investment provisions in the Trans- Pacific Partnership (TPP), the Transatlantic Trade & Investment Partnership, and the U.S.-China Bilateral Investment Treaty. He is widely recognized as one of the foremost experts on investment protection in the world.
Patrick has received several awards and serves on multiple boards. He is band ranked in Chambers, recommended in the Legal 500, and the youngest person ever listed as a “Global Thought Leader” the highest designation in the peer ranked Who’s Who Legal: Arbitration, where he is recognized as “an incredible advocate,” “whose razor-sharp mind is unmatched” and who is a “leader in public international law and investment treaty arbitration.”
He is an adjunct professor at Georgetown University Law Center where he teaches two courses on international courts and tribunals and investment arbitration. Prior to this appointment, he taught at Columbia Law School, Harvard Law School and Yale Law School.
Patrick is on the panel of arbitrators for the Hong Kong International Arbitration Centre (HKIAC), the Korean Commercial Arbitration Board (KCAB) and the International Center for Settlement of Investment Disputes (ICSID).
Client commentary: “Patrick Pearsall is an absolute rock star of Public International Law. He has an intelligence, experience and bearing that would be impressive in a lawyer nearing the end of his career. To see it in one who is just hitting his peak performing years is rare and special. There is no lawyer working in bilateral investment treaty work whom I rate more highly.”
Expertise
Practices
Litigation, Arbitration and Investigations
Office
Washington, D.C.
Allen & Overy LLP
1101 New York Avenue, NW
Washington, D.C.
20005
Qualifications
Professional
Admitted: District of Columbia Bar, 2009
Admitted: Bar of the State of New York, 2006
Academic
J.D., Law, Columbia University School of Law, 2005
B.A., English and Political Science, magna cum laude, Columbia College, 2002
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Expertise
Practices
Litigation, Arbitration and Investigations
Office
Washington, D.C.
Allen & Overy LLP
1101 New York Avenue, NW
Washington, D.C.
20005
Qualifications
Professional
Admitted: District of Columbia Bar, 2009
Admitted: Bar of the State of New York, 2006
Academic
J.D., Law, Columbia University School of Law, 2005
B.A., English and Political Science, magna cum laude, Columbia College, 2002