Mark Sullivan leads Grant Thornton’s Advisory Practice for the Central Region. He also serves as the leader of the Forensic Advisory Services practice in Chicago. Mark specializes in corporate investigations, fraud prevention and detection, and litigation support. For more than 25 years, Mark has worked with companies and their counsel worldwide to investigate frauds, develop and implement anti-fraud programs, and identify vulnerabilities within their organizations. His advanced interviewing skills and his team of forensic accountants, eDiscovery and computer forensic professionals provide an unparalleled response to complex investigations, compliance and litigation matters.
Vendor Fraud. Mark managed a team in a complex analysis to prove allegations of kickbacks and improper vendor relationships at a major consumer products firm. The investigation resulted in several criminal convictions and civil judgments in excess of $100 million.
Compliance. Mark was engaged to provide an independent review of an internal investigation of possible False Claims Act violations on behalf of a Fortune 50 company. His team of forensic accountants and IT specialists reviewed and tested the corporation’s findings that were presented to the Department of Justice.
Anti-Bribery and Corruption. Mark has built a team of professionals in the Central region that focus their efforts on FCPA and other corruption investigations. Mark has led matters in the Americas, Europe, Africa and Asia.
Mark served as a Managing Director and national practice leader for Kroll’s corporate loss prevention practice. Prior to Kroll he was the loss prevention practice leader at Deloitte. Earlier in his career, he served as a partner in a regional consulting firm and senior consultant in the fraud and security practice at Arthur Andersen.
- Forensic, investigative and dispute services
Professional qualifications and memberships
Center for Interviewing Standards and Assessment, Advisory Committee Member
National Immigrant Justice Center, Leadership Board Member
American Society for Industrial Security
Certified Fraud Examiner (CFE)
Certified Forensic Interviewer (CFI)
Certified Protection Professional (CPP)
Choose DuPage, Board Member
Union League Club of Chicago
BS, Administration of Justice, Southern Illinois University
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