"Diamond" Joe Gutnick, the former president of the Melbourne Demons AFL club, has been banned from managing corporations for four years by the financial regulator.
The Australian Securities and Investments Commission found the fallen mining magnate acted improperly and failed to meet his obligations as director of three companies between June 2016 and March 2020.
The three companies - Axis Consultants, Merlin Diamonds and Legend International Holdings - have all been deregistered or placed into liquidation.
Among Mr Gutnick's indiscretions, ASIC found he allowed a company to trade while insolvent, failed to ensure record-keeping requirements were met and failed to assist liquidators when requested.
Legend and Merlin together owed more than $43 million to unsecured creditors, including local councils, an Aboriginal land council and the Queensland and Western Australian governments.
Mr Gutnick declared bankruptcy in 2016, owing creditors more than $275.5 million.
Merlin Diamonds was wound up in 2020 after ASIC made a successful application to the Federal Court on insolvency grounds.
Unless he successfully appeals ASIC's decision at the Administrative Appeals Tribunal, Mr Gutnick will be disqualified from managing corporations until March 3, 2028.