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Home Our People Mark Calnan

Mark Calnan


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Mark is a Principal in Withum’s Forensic and Valuation Services team and has extensive experience providing Anti-Money Laundering (AML), fraud investigation, and litigation investigative support services. Prior to joining Withum, he managed investigative matters at Doyle Carden Group in New York City, including due diligence and background investigations, as well as civil litigation and criminal defense investigative support services. Previously, Mark conducted AML investigations at Fidelity Investments in Merrimack, New Hampshire.

Mark served as an FBI special agent for 25 years in Minneapolis, New York and Newark field offices. His work in the FBI focused on organized crime, white-collar crime, drug trafficking and money laundering. He was the case agent for a landmark international undercover investigation linking Chinese Southeast Asian heroin importers with Sicilian Mafia drug networks in North America.

Mark is a U.S. Army veteran and graduated from Merrimack College in North Andover, Massachusetts with a Bachelor of Arts in sociology.

Withum isn’t just a job— we’re a family, and we carry that spirit together in everything we do. We live the Withum Way. We are catalysts for growth and success.

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