The company has tightened rules on fair dealing, auditing, use of emails and corporate entertaining after a damning investigation of its former management revealed widespread malpractice.

A section of the new code states: 'If an employee is having difficulty determining whether a specific gift or entertainment item lies within the bounds of acceptable business practice, he or she should ask these guiding questions: Is it legal? Is it clearly business-related? Is it moderate, reasonable, and in good taste? Would public disclosure embarrass Hollinger?'

Hollinger filed its new code of conduct at the US watchdog, the Securities and Exchange Commission on Friday, The Financial Times reported.