Photograph of Aryeh S. Portnoy

Aryeh S. Portnoy


Aryeh S. Portnoy is partner in Crowell & Moring's Litigation Group and head of the firm's Hospitality Practice. Resident in the Washington, D.C. office, Aryeh joined Crowell & Moring in 1998. He focuses on complex cross-border and domestic litigation in U.S. state and federal trial and appellate courts. He has counseled and represented corporate, non-profit, and individual clients as well as foreign and domestic government agencies and officials in all phases of litigation.

Aryeh represents hospitality companies in domestic and international litigation and arbitration matters, including disputes regarding management agreements and development projects, government contracts disputes, and antitrust litigation. Aryeh's recent representations include the successful litigation of a high profile dispute on behalf of a major hotel management company regarding the development of a 1200-room luxury convention center hotel, and the successful arbitration on behalf of another major hotel management company in a multi-million dollar dispute over the applicability of a performance standard clause in a hotel management agreement. Aryeh's recent representations also include a management dispute regarding a resort in the Caribbean and a U.S. class action regarding online pricing of hotels.

Aryeh also has substantial experience representing foreign and domestic clients in international and cross-border matters. These matters range from complex international commercial disputes involving foreign sovereign entities (including central banks) to tort claims, including wrongful death actions against public and private defendants under the Federal Tort Claims Act and state common law, and lawsuits against foreign governments on behalf of victims of terrorism. Aryeh counsels clients and has litigated extensively under the Foreign Sovereign Immunities Act (FSIA) and is the co-author and editor of an annual review of litigation under the FSIA.

Aryeh's experience also includes the representation of U.S. and local government agencies and officials. He has successfully represented officials of the United States in several matters arising from the performance of their public duties, including obtaining dismissal of all claims against a former Army Brigadier General in litigation arising from the war in Iraq. He also has represented the District of Columbia Public Schools in a major class-action under the Individuals with Disabilities Education Act.

In addition to his litigation work, Aryeh also has provided compliance counseling and training to major U.S. and multinational corporations on compliance with the U.S. Foreign Corrupt Practices Act (FCPA).

Beyond these specialty areas, Aryeh has a robust general litigation practice in which Aryeh has litigated extensively on behalf of U.S. and international corporate and individual clients in civil and criminal matters in a variety of areas including commercial disputes, white collar and securities fraud litigation, false claims act and qui tam litigation, and tax litigation. Aryeh recently obtained dismissal of all counts in a securities fraud class action under the PSLRA. Aryeh's experience also includes the successful defense of the American Psychiatric Association in a major pharmaceutical class action litigation, the dismissal (and settlement) of securities fraud claims against a major financial institution as underwriter in securitized asset offerings, and the acquittal on all counts of the president of a major marine construction company who was charged with criminal violations of the Sherman Antitrust Act.

Aryeh has an active pro bono practice, in which he has handled over 35 contested custody disputes on behalf of indigent clients in the District of Columbia. In these matters, Aryeh has represented parents and grandparents seeking custody, and also has been appointed on many occasions by District of Columbia Superior Court judges as Guardian ad Litem for children in the District of Columbia neglect system. Aryeh has been recognized for his pro bono custody work by receiving the "Idealist of the Year" award from the the Washington D.C. Chapter of City Year, and the Klepper Prize for Volunteer Excellence by the Legal Aid Society of the District of Columbia. 


  • Columbia University (1995) magna cum laude
  • New York University School of Law (1998)


Admitted to practice: New York, District of Columbia, U.S. Court of Appeals for the District of Columbia Circuit, U.S. Courts of Appeals for the Fifth and Eleventh Circuits, Southern District of New York, U.S. District Court for the District of Columbia.


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Litigation & Trial

Commercial Litigation


White Collar and Regulatory Enforcement

Foreign Corrupt Practices Act

False Claims Act and Procurement Fraud

Administrative Law and Regulatory

International Dispute Resolution

Latin America Practice

International Litigation

False Claims Act and Procurement Fraud

Anti-Corruption, Foreign Corrupt Practices Act (FCPA) and U.K. Bribery Act

International Dispute Resolution

Israel Practice

Litigation and Dispute Resolution

International Terrorism Litigation

Show more practices…

  • Representation of major hotel management company in dispute with Owner over termination of management agreement for Caribbean resort.
  • Representation of a South American Central Bank in litigation with global bank over alleged violations of investment guidelines for securities lending program.
  • Representation of major U.S. energy company in multi-million-dollar tax dispute.
  • Representation of victims of terrorism in FSIA litigation arising from attacks on U.S. embassy and U.S. embassy annex in Beirut, Lebanon.
  • Representation of victims of terrorism in FSIA litigation arising from attack on U.S. embassy in Nairobi, Kenya.
  • Successful representation of CFO in securities fraud class action brought pursuant to the PSLRA.
  • Successful representation of major hotel management company in multi-million dollar dispute over applicability of performance standard in hotel management agreement.
  • Successful representation of major hotel management company in dispute over development of 1,200 room luxury convention-center hotel.
  • Pugh v. Socialist People's Libyan Arab Jamahiriya, et al. (D.D.C.) ($6.1 billion judgment arising from terrorist bombing of UTA 772 in September 1989).
  • Smith v. Hope Village, Inc. , 481 F. Supp.2d 172 (defeating summary judgment motion by DC Halfway House in litigation arising from murder of 9-year old girl by previously released resident).
  • In re Iraq and Afghanistan Detainees Litig. , 479 F. Supp.2d 85 (dismissal of all claims against former Army Brigadier General in litigation arising from war in Iraq).
  • Carney v. United States , 182 Fed. Appx. 295 (affirmance of dismissal of all claims against current and former agents of Office of Thrift Supervision).
Crowell & Moring Named to Global Arbitration Review’s 2021 “GAR 100” List (July 20, 2021)
Firm News / Announcement
Crowell & Moring Partner Ian A. Laird Named One of Latin America’s Top 100 Lawyers (July 1, 2021)
Firm News / Announcement
"DoE’s New Title IX Regulations: What School Administrators Need to Know," Regulatory Alert (May 13, 2020). Contacts: Amanda Shafer Berman, Laurel Pyke Malson, Aryeh S. Portnoy, Eli Berns-Zieve
Client Alert / Newsletter
"Five Considerations as You Prepare for the Release of the Final Title IX Regulations," (May 4, 2020). Contacts: Amanda Shafer Berman, Laurel Pyke Malson, Aryeh S. Portnoy, Rebecca L. Springer, Eli Berns-Zieve
Client Alert / Newsletter
Global Investigations Review Names Crowell & Moring’s White Collar & Regulatory Enforcement Group to “GIR 100” Fifth Year in a Row (November 5, 2019)
Firm News / Announcement
Apollo Global Management Obtains Temporary Injunction Against Insurance Lawsuit Insurance Business America (July 16, 2019)
Press Coverage
Bermuda Court Orders Halt To US Lawsuit Against Apollo Financial Times (July 15, 2019)
Press Coverage
"Arbitration – Unlocking the Promise of Arbitration," Crowell & Moring's Litigation Forecast 2018 (January 2018). Contributor: Aryeh Portnoy.
Crowell & Moring Partner Stuart Newberger Named American Lawyer’s Litigator of the Week for Winning Argument in Terrorism Ruling against Sudan (August 4, 2017)
Firm News / Announcement
Federal Appeals Court Affirms Multi-Billion Judgment for Victims of 1998 U.S. Embassy Bombings in Kenya and Tanzania (July 30, 2017)
Firm News / Announcement

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Crowell & Moring LLP is an international law firm with offices in the United States, Europe, MENA, and Asia that represents clients in litigation and arbitration, regulatory and policy, and transactional and corporate matters. The firm is internationally recognized for its representation of Fortune 500 companies in high-stakes litigation and government-facing matters, as well as its ongoing commitment to pro bono service and diversity, equity, and inclusion.

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