Chairman James McClements told the company's annual general meeting on Thursday that Mr Ellison's historic dealing with Far East Equipment Holdings - a company he had a stake in and that sold Mineral Resources equipment - showed a lack of "judgment and integrity that we would expect of our managing director."
Mr Ellison also at times used company resources for personal matters, although there was a process for Mineral Resources to be repaid, Mr McClements said.
The board announced on November 4 that Mr Elllison would pay a penalty of $8.8 million and leave as managing director within the next 12 to 18 months, once a new successor is found.
In May 2023 Mr Ellison paid the Australian Taxation Office $3.9 million. (Lukas Coch/AAP PHOTOS)
Mr Ellison told shareholders that many years ago, he had been a partner in a private company and made a "judgment error" regarding reporting of personal taxes.
Mr Ellison self-reported the matter to the Australian Tax Office in 2021 and in May 2023 paid the tax office $3.9 million, including interest and penalties.
"So I put that behind me, and I deeply regret the impact this has had on the business and our people," he said.
"I can't stress enough how much I hate what I've done. It's a dark cloud in my life that I'll live with forever. I want everyone to know I deeply regret that that error in judgment that I made back there."
Mr Ellison said he took full responsibility for his mistakes but had also built a great company that had employed thousands of people, delivered extremely good returns for shareholders and huge benefits to Australia.
"This business will keep doing that for a long time to come," promised Mr Ellison, who founded Mineral Resources 32 years ago.
The annual meeting was continuing on Thursday afternoon.
