Ted Theisen is a Senior Managing Director within the Cybersecurity Practice at Ankura Consulting Group, located in the Washington, DC office. He has more than 17 years of experience in information technology including designing information security programs, responding to complicated cyber incidents, and enhancing information security. Mr. Theisen has significant investigative experience leading numerous highly technical and complicated cyber incidents requiring the direction of multi-discipline and multi-national collaboration resulting in efficient and effective results.

Prior to joining Ankura, Mr. Theisen served as a Managing Director at an international litigation support firm where he developed and built a cyber- risk division including services such as incident response, risk assessments, as well as managed security services. He was directly responsible for overseeing all data breach matters and ensured a rapid response, adequate preservation of evidence, and ultimately identified the root cause of all breaches, as well as any exfiltrated, compromised, or exposed intellectual property.

In addition to his contributions in the private sector, Mr. Theisen also has notable government service. He served as a Special Agent in the Federal Bureau of Investigation where he investigated cyber related matters for the duration of his tenure, which included computer intrusions, cyber counterintelligence, and cyber counterterrorism matters. Mr. Theisen also served as the Branch Chief of Cyber Integrity for one year at the Executive Office of the President where he provided information risk management, information assurance, and eDiscovery leadership to The White House, Executive Residence, Office of the Vice President, and all other peripheral entities of the White House.

Notable Investigations that Mr. Theisen has conducted:

  • Cyber Extortion of a Scientific Company – A global company was threatened by an unknown subject with releasing intellectual property to the public unless a ransom was paid. Mr. Theisen lead a team of investigators to identify exposed data within the company, potential exfiltration vectors, and vulnerabilities that fostered unauthorized access
  • Cyber Domestic Terrorism Investigation – A US based food company was threatened by a domestic terrorism organization over the Internet. Mr. Theisen lead the investigation to successful attribution to the attacker and subsequent arrest
  • Insider Threat Investigation of a Financial Institution – A US based financial institution suspected escalation of privileges by a system administrator. Mr. Theisen was able to lead a team to surreptitiously identify unauthorized activity of the main subject of the investigation with minimal interruption to business functionality
  • Data Breach of Health Care Facility – A large US based health care system suffered a breach of Protected Health Information (PHI). Mr. Theisen lead the team to identify exposed data as well as the vector of compromise.
  • Amerithrax Investigation – Mr. Theisen served on a large team of special agents that responded to the residence of Dr. Bruce Ivans, as well as his laboratory at United States Army Medical Research Institute of Infectious Disease (USAMRIID) ensuring ample preservation of evidence in a volatile environment
  • Numerous Cyber Counterintelligence investigations in which the tradecraft and techniques of adversaries to the United States were identified
  • Several investigations associated with internet threats made to high ranking public officials in which rapid attribution of the attacker was necessary


New Agent Training, FBI Academy - Quantico, Virginia

BS, Biology, University of Nebraska at Omaha 


Certified Radiological Worker 2, US Department of Energy

FBI Hazardous Materials Response Team - investigated chemical, biological and radiological threats

MCSE and MCP+I Certified


Society of Former Special Agents of the FBI


US Attorney Award, District of Delaware - contributions to Internet Crimes Against Children, 2010

Dedicated service award for contributions to the Terrorist Screening Operations Unit (TSOU), 2008

Exemplary service award for achievements at National Joint Terrorism Task Force (NJTTF), 2006