Sylvia G. Costelloe

Sylvia is a trusted advisor in ArentFox Schiff’s International Trade practice, focusing on export controls, economic sanctions, CFIUS, and antiboycott matters.
Sylvia G. Costelloe

Sylvia regularly advises clients with respect to the Export Administration Regulations (EAR), International Traffic in Arms Regulations (ITAR), and Office of Foreign Assets Control (OFAC) sanctions and embargoes. She helps large and small US and non-US companies understand and comply with the complicated US laws and regulations governing exports and re-exports of goods, software, services, and technology. Sylvia advises clients on international regulatory issues, including civilian and military export controls, economic sanctions, and antiboycott regulations. She frequently assists clients with license applications, commodity classifications, compliance program design and implementation, audits, and voluntary disclosures to various government agencies, including the Directorate of Defense Trade Control (DDTC), the Bureau of Industry and Security (BIS), and OFAC.

Sylvia also counsels clients on the Committee on Foreign Investment in the United States (CFIUS) and its expanded authority under the Foreign Investment Risk Review Modernization Act (FIRRMA). She advises both investors and target companies on transactions involving critical technology, and sensitive personal data, including mergers and acquisitions, venture capital investments, and private equity transactions. She advises clients on the regulatory implications of various transactions and regularly prepares filings for CFIUS review. She also advises clients on the new export controls on emerging and foundational technologies, as mandated by the Export Control Reform Act of 2018 and how they intersect with CFIUS’s jurisdiction.

Sylvia has also counseled clients on Foreign Corrupt Practices Act (FCPA) and business ethics-related compliance policies and procedures. She has experience in various industries, including telecommunications, electronics, information technology, chemicals, and industrial manufacturing.

Previous Work

Prior to joining ArentFox Schiff, Sylvia served in a clerkship with Judge Kim R. Gibson (Western District of Pennsylvania).

Publications, Presentations & Recognitions



Life Beyond the Law

Sylvia grew up in Europe and Asia, and is fluent in German and French. She enjoys hiking, skiing, rock climbing, reading, and traveling to Europe.


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