Tatiana O. Sullivan

Tatiana O. Sullivan

Counsel, National Security; CFIUS

Tatiana Sullivan is a lead counsel on Defense Counterintelligence and Security Agency (DCSA), Committee on Foreign Investment in the United States (CFIUS) and government contract matters at Skadden.


Ms. Sullivan has worked on issues involving Foreign Ownership, Control or Influence (FOCI) under the National Industrial Security Policy Operating Manual (NISPOM); CFIUS; ex-U.S. foreign direct investment (FDI) screening; International Traffic in Arms Regulations (ITAR); Export Administration Regulations (EAR); Federal Acquisition Regulations (FAR); and Defense Federal Acquisition Regulations (DFARS).

Ms. Sullivan provides advice to clients interested in making investment transactions in the U.S. or in other jurisdictions subject to FDI screening regulations. She worked for several years at the U.S. Department of Defense (DoD), including serving as associate director of CFIUS operations and regulatory affairs for the department. In her prior roles, Ms. Sullivan was the staff lead at DoD for the negotiation and implementation of the Foreign Investment Risk Review Modernization Act (FIRRMA). She also was responsible for reviewing investment transactions before CFIUS, developing risk analyses and making recommendations to political leadership at the DoD and CFIUS. Ms. Sullivan served as the lead negotiator for several high-profile mitigation agreements and was responsible for developing, implementing and monitoring a range of national security agreements. In addition, she was actively involved in the discussions with allies and partners looking to develop FDI screening mechanisms.

Ms. Sullivan frequently supports clients interested in investing or acquiring U.S. technology or companies engaged in activities subject to the EAR or ITAR. Among her prior roles, she served as a lead export control analyst at the Defense Technology Security Agency, where she represented the DoD on the Operating Committee and supported senior policy officials on the Advisory Committee on Export Policy, working with counterparts from the departments of State, Commerce and Energy to analyze and adjudicate license proposals with significant foreign and national security policy implications.

Ms. Sullivan worked closely with counterparts at the Defense Counterintelligence & Security Agency (DCSA) to address and adjudicate policy implications for the protection and security of classified information and programs. Since joining Skadden, she has worked closely with clients looking to develop, expand or invest in companies subject to the NISPOM, helping clients navigate complex compliance matters while helping them to optimize their business operations under the NISPOM.

Ms. Sullivan frequently advises clients on the acquisition, integration and post-closing activities for both classified and unclassified government contract businesses, helping clients navigate key regulatory and security requirements under the FAR and DFARS. She also assists buyers and sellers in navigating the regulatory aspects of complex M&A deals involving government contractors, including due diligence reviews and contract negotiations. Her clients include companies in the aerospace, communications, defense, manufacturing, real estate and technology industries.



  • J.D., Washington College of Law, American University, 2010 (Executive Editor, American University Business Law Review)
  • B.A., College of the Holy Cross, 2007 (cum laude)


  • New York
  • District of Columbia

Tatiana O. Sullivan

Counsel, National Security; CFIUS