Harry M. Markopolos or Harry Markopoulos (born October 22,
1956 in Erie, Pennsylvania) is a former securities industry
executive turned independent financial fraud investigator
for institutional investors and others seeking forensic
accounting expertise. He has risen to prominence as an early
and unheeded whistleblower of suspected securities fraud by
Bernard Madoff, tipping off the United States Securities and
Exchange Commission (SEC) repeatedly, both orally and in
writing starting in 1999, when he argued that it was not
legally possible for Madoff to deliver the returns he had
claimed to deliver.