Matthew D. Slater’s practice focuses on international investment-treaty and commercial arbitration and litigation involving the highest stakes and cutting-edge issues.

In his international arbitration and litigation practice, Matt often represents foreign sovereign governments and government agencies and instrumentalities. He also regularly represents clients in international litigation in a diverse range of matters in U.S. courts often involving cross-border coordination with courts around the world.

Matt is also active in the firm’s pro bono practice.

Matt joined the firm in 1985, became a partner in 1992, and became a senior counsel in 2021. In 1995, he was appointed principal deputy general counsel of the U.S. Air Force, where he worked in government service until rejoining the firm in 1999. Matt was responsible for the department’s alternative dispute resolution program and for overseeing major litigation concerning national security information and the military and state secrets privilege, tort claims, environmental claims, bid protests, contract claims, and base closures, as well as for a wide range of non-litigation matters. He was awarded the Air Force Decoration for Exceptional Civilian Service.

Notable Experiences

  • Robert Bosch GmbH and Robert Bosch LLC as lead counsel in multidistrict litigation and other proceedings in the United States arising from allegations that Volkswagen, Audi and Porsche used equipment supplied by Bosch to manipulate the results of diesel vehicle emissions tests; and lead counsel in multidistrict litigation in the United States alleging diesel emissions manipulation by Fiat Chrysler Automobiles, as well as in diesel emissions litigation involving other vehicle manufacturers, including General Motors, Mercedes Benz, Ford, and BMW.

  • The Republic of Argentina, together with the Procuración del Tesoro de Argentina, in claims brought at the International Centre for Settlement of Investment Disputes (ICSID) under the Argentina-Italy bilateral investment treaty concerning interests in Argentine bonds, alleging unfair and discriminatory treatment and expropriation and seeking billions of dollars in damages. It was the first attempt to pursue a mass claim – more than 60,000 claimants in a single proceeding – in an ICSID arbitration and also involved a novel attempt to use investment treaty arbitration to challenge a sovereign bond default and debt restructuring.

  • The Republic of Argentina in its defense in federal court against recognition and enforcement of various bilateral investment treaty awards, including as counsel of record in the U.S. Supreme Court in BG Group Plc v. The Republic of Argentina, decided in March 2014, which is the first case involving an arbitral award made under an investment treaty considered by the Supreme Court.

  • YPF S.A., a major Argentine oil and gas producer, in a successful commercial arbitration and, separately, in defending against enforcement of an unrelated Argentine arbitral award in federal court in Delaware.

  • The Government of Japan in proceedings commenced by Australia and New Zealand before the International Tribunal for the Law of the Sea and then before a tribunal formed under the United Nations Convention on the Law of the Sea relating to international fishing rights (Southern Bluefin Tuna case).

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  • Member, Members Consultative Group, Restatement Third, Project on The U.S. Law of International Commercial Arbitration, American Law Institute
  • Former Member, ICC Task Force on Arbitration Involving States or State Entities
  • Director, Washington Lawyers’ Committee for Civil Rights and Urban Affairs
  • Trustee, Lawyers’ Committee for Civil Rights Under Law


Second Circuit Rules Foreign State-Owned Bank Does Not Have Sovereign Immunity From Criminal Prosecution,” Cleary Gottlieb Alert Memo, November 23, 2021

Second Circuit Dismisses Antitrust Claims Against Chinese Pharmaceutical Companies Based on International Comity,” Cleary Gottlieb Alert Memo, September 2, 2021

U.S. Supreme Court Revisits the Contours of Specific Personal Jurisdiction,” Cleary Gottlieb Alert Memo, April 6, 2021

U.S. Supreme Court Defines Contours of FSIA’s Expropriation Exception,” Cleary Gottlieb Alert Memo, February 8, 2021 

SDNY District Court Rules Foreign Sovereigns Are Not Immune From Criminal Jurisdiction In U.S. Court,” Cleary Gottlieb Alert Memo, October 9, 2020 

Class & Collective Action Group Newsletter,” October 6, 2020 

Circuit Split Intensifies Over Use of 28 U.S.C. § 1782 to Obtain Discovery for Use in Private International Arbitration,” Cleary Gottlieb Alert Memo, July 13, 2020

International Arbitration in the Time of COVID-19: Navigating the Evolving Procedural Features and Practices of Leading Arbitral Institutions,” Cleary Gottlieb Alert Memo, July 10, 2020

Supreme Court Holds That New York Convention Does Not Preclude Non-Signatories From Invoking State Law Principles To Compel Arbitration,” Cleary Gottlieb Alert Memo, June 3, 2020 

SCOTUS Case Sets Limits on Agency Deference,” Cleary Gottlieb Alert Memo, July 3, 2019

Supreme Court Invalidates the Requirement to Show ‘Substantial Competitive Harm’ to Protect Private-Party Confidential Information Under FOIA Exemption 4,” Cleary Gottlieb Alert Memo, June 26, 2019

Second Circuit Holds General Statements of Regulatory Compliance Cannot Sustain Securities Fraud Claim,” Cleary Gottlieb Alert Memo, March 8, 2019 (republished by the Harvard Law School Forum on Corporate Governance and Financial Regulation, March 23, 2019)

Supreme Court Confirms Arbitrators Decide Threshold Issues,” Cleary Gottlieb Alert Memo, January 9, 2019

The HKIAC Council Approves the 2018 Administered Arbitration Rules,” Cleary Gottlieb Alert Memo, October 22, 2018

Second Circuit Holds That U.S. Law Firm Need Not Produce Foreign Client’s Documents Pursuant to 28 U.S.C. § 1782,” Cleary Gottlieb Alert Memo, July 2018

SCOTUS: American Pipe Tolling Doesn’t Apply to Successive Class Actions,” Cleary Gottlieb Alert Memo, June 2018

Jurisdictional and Forum Requirements for ICSID Award Recognition Against Foreign Sovereigns: Recent Developments and Debates,” Mealey’s International Arbitration Report, November 2017 

CFPB Issues Final Rule on Arbitration Agreements in Financial Products and Services Contracts,” The Banking Law Journal, October 2017

Second Circuit Confirms That an Arbitral Award That Has Been Nullified at the Seat of the Arbitration Should Rarely Be Enforced,” July 27, 2017

CFPB Issues Final Rule on Arbitration Agreements in Financial Products and Services Contracts,” July 13, 2017

U.S. Supreme Court Holds That State Courts Lack Specific Personal Jurisdiction to Entertain Non-Residents’ Claims for Injuries Not Connected to In-State Conduct,” June 20, 2017

U.S. Supreme Court Reaffirms That Corporate Defendants Are Subject to General Personal Jurisdiction Only Where They Are ‘At Home,’” May 30, 2017 (republished in the Harvard Law School Forum on Corporate Governance and Financial Regulation on June 14, 2017)

Supreme Court Adopts Exacting Approach to Jurisdictional Inquiry Under FSIA’s Expropriation Exception,” May 2, 2017

2009-2017: Written annual articles on “International Litigation: The Act of State Doctrine” for The Year in Review (ABA Section of International Law)

CFPB Issues Rulemaking on Arbitration Agreements in Financial Products and Services Contracts,” May 16, 2016

2009-2015: Written articles annually on “International Litigation: The Act of State Doctrine” for The Year in Review  (ABA Section of International Law)

“Seventh Circuit Creates Novel Rule That Parties May Waive Objection to Appointment of Substitute Arbitrators Unless They Immediately Apply to a Court for Appointment,” MEALEY’S International Arbitration Report, December 2009

“The Energy Charter Treaty: A Brief Introduction to its Scope and Initial Arbitral Awards,” Alternative Dispute Resolution in the Energy Sector (Association for International Arbitration), May 2009

“On Annulled Arbitral Awards and the Death of Chromalloy,” Arbitration International, April 2009