A US software tycoon has been charged over the biggest alleged tax evasion scheme in American history.
Robert Brockman, chief executive of Reynolds and Reynolds, is alleged to have hidden $2bn (£1.5bn) in income from tax authorities over two decades, using a network of offshore companies.
He was also charged over an alleged fraud scheme involving debt securities.
Mr Brockman appeared by teleconference at a federal court in Houston, Texas, and pleaded not guilty to the charges.
Prosecutors said they were alerted to his alleged activities by fellow billionaire Robert Smith, who they say testified against him to avoid prosecution himself. Mr Smith shot to fame last year after giving a speech at Morehouse College's graduation ceremony, promising to pay all student debt for 2019 graduates.