Gina Rinehart's Hancock Prospecting has finally bowed to pressure from the corporate watchdog, with financial reports released over the Christmas break revealing the mining billionaire's main private company booked profits of almost $1.9 billion between 2009 and 2011.
Hancock Prospecting's only working mine is the Hope Downs joint venture with Rio Tinto, which operates the Pilbara mine.
Financial results lodged with the Australian Securities and Investments Commission on Christmas Eve reveal the company made an after tax profit of $688.3 million in the 2009/2010 financial year, which lifted to $1.2 billion in the 2010/2011 period as iron ore prices surged.
The accounts show that Hancock was sitting of a $1.68 billion cash pile in June 2011.
Mrs Rinehart is fiercely protective of her privacy, and fought a 16-month battle with the Australian Securities and Investments Commission to avoid the public release of Hancock Prospecting's financial reports.
ASIC ordered the company to submit annual reports for the company's 2009/2010 and 2010/2011 financial reports in August 2011, with Mrs Rinehart's private company arguing the regulatory requirement would reveal operating costs at its operations and potential reduce its negotiating power.
The dispute flared as three of Mrs Rinehart's estranged children launched a legal push to win a non-controlling 24 per cent stake in the multi-billion dollar company.
But the company appears to have failed in its bid for secrecy, releasing the financial documents just before Christmas.