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Cyril (Cy) Brennan focuses his practice on international trade and national security regulatory and compliance matters, with an emphasis on U.S. export controls, economic sanctions, and foreign direct investment matters. Cy provides clients experience across a broad array of U.S. international trade regulatory frameworks, including the International Traffic in Arms Regulations (ITAR), the Export Administration Regulations (EAR), the various U.S. sanctions programs administered by the Treasury Department’s Office of Foreign Assets Control (OFAC) and the Department of Commerce’s anti-boycott regulations. His clients include a wide of array of companies in the aerospace, defense, space and hi-tech sectors.

Cy also assists clients in complex matters involving the national security regulatory space. He focuses on representing clients before the Committee on Foreign Investment in the United States (CFIUS) in the context of mergers and acquisitions, as well as private equity, real estate, and venture capital investments. In this capacity he also advises on the National Industrial Security Program, including negotiating foreign ownership, control, or influence (FOCI) mitigation instruments with the Defense Counterintelligence and Security Agency (DCSA).

Prior to joining Greenberg Traurig, Cy served in the United States Senate in a foreign relations capacity, and later worked in-house at one of the world’s largest aerospace and defense companies.

Concentrations

  • Export controls
  • Economic sanctions
  • Committee on Foreign Investment in the United States (CFIUS)
  • Aerospace and Defense
  • Space and Satellite regulatory matters
  • Anticorruption compliance
  • Foreign ownership, control or influence (FOCI)

Capabilities

Experience

  • Represented Carrick Capital Partners in connection with its Series B Investment in Bishop Fox. Bishop Fox provides offensive security solutions ranging from continuous penetration testing, red teaming, and attack surface management to product, cloud and application security assessments.
  • Represented Crestview Partners in connection with the acquisition of Emerald EMS, an electronics manufacturing services provider specializing in high-mix, low-volume engineering, design, prototyping, testing, assembly and lifecycle support services for blue-chip original equipment manufacturers across a range of end markets.

Recognition & Leadership

  • Listed, Latin Lawyer, "Latin Lawyer 250 - Practice Recognition: Anti-Corruption Investigations and Compliance," 2020-2025
  • Team Member, National Law Journal, “Washington, D.C. Litigation Department of the Year - White Collar Defense & Special Investigations,” 2022
  • Team Member, "Corporate & Finance - International Counsel in Latin America (Florida-Based)," Chambers Latin America Awards, 2017
  • Elected Member, International Institute of Space Law, 2024
  • Member, American Bar Association
    • Steering Committee, Aerospace & Defense Industries Committee, Section of International Law and Practice (2014-2015)

Credentials

Education
  • J.D., Northwestern Pritzker School of Law, 2008
    • Senior Editor, Northwestern Journal of International Law and Business
  • B.A., cum laude, Yale University, 2003
Admissions
  • District of Columbia
  • Illinois
Languages
  • French, Conversational
  • Spanish, Conversational

Related Capabilities

International Trade Export Controls & Economic Sanctions White Collar Defense & Investigations Regulatory & Compliance Government Contracts Digital Infrastructure, Data Center and Cloud Computing Latin America Practice Defense, Aviation & Space Space & Satellite