Gina Rinehart’s billion-dollar resources company, Hancock Prospecting, has failed to file its annual accounts for the past two years, a failure which the corporate regulator was at a loss to explain last night.

John Hancock, one of the three Rinehart children in dispute with Mrs Rinehart over the family trust which controls almost a quarter of Hancock Prospecting Pty Ltd, confirmed to BusinessDay yesterday that he had been unable to obtain financial statements either for the trust or the company.

Under the disclosure requirements of the Corporations Act, a company is required to lodge annual accounts within four months of the end of the financial year.

Not only are Hancock Prospecting’s financial reports for 2010 and last year missing but the reports for each year from 2006 to 2009 were each filed more than a year late.

A spokesman for Mrs Rinehart said the company had no comment.

A spokesman for the Australian Securities & Investments Commission said it declined to comment on specific companies. Its chairman, Greg Medcraft, was unavailable.

Jeffrey Knapp, the accounting academic at the University of NSW who brought to light the failure of the collapsed airline Ansett to produce audited accounts for eight

years, said the regulator was “missing in action again”.

“Members of the public, including all of the children of Mrs Rinehart, are entitled by law to access the annual financial report of HPPL [Hancock Prospecting] from ASIC’s public data base around four months after the relevant financial year end,” he said.

“ASIC manages the public data base for companies. ASIC must know about the missing and late financial reports of HPPL.

”But there is no evidence of a response to the financial reporting holes in its database for big companies like HPPL, Ansett Australia and a raft of others.”

Hancock Prospecting, which controls major iron ore properties in Western Australia and coal in Queensland, had $1.46 billion in assets at its last available annual report in 2009.

In that year it recorded a profit of $227 million on $738 million in revenues. There were $23 million of loans made to related parties. Audit and tax fees to PwC were $729,000.

The Hope Margaret Hancock Trust – subject of a bitter public dispute – holds a 23.45 per cent voting stake in HPPL. It was created by Mrs Rinehart’s father, Lang Hancock, who listed his four grandchildren as beneficiaries.

The trust receives dividends from the company, some of which are distributed to the children. HPPL has 6000 voting shares. Mrs Rinehart holds 4593 and the trust 1407, said a statement of defence filed by Mrs Rinehart’s lawyers.

Also in the court documents revealed this week, Jay Newby, the chief financial officer of Hancock Prospecting, calculated the value of each child’s share of the trust at $600 million.

That calculation was in an email on September 4 last year, based on an estimate of Mrs Rinehart’s wealth of $10.3 billion.

However, subsequent asset sales have increased her wealth substantially, on paper at least.

The Bloomberg Billionaires Index puts Mrs Rinehart’s net worth at $US20.2 billion, a figure which would value each child’s stake at about $US1.18 billion ($1.12 billion), drawing on Mr Newby’s calculations.