Big G family feud is bringing the taxman, regulator and lawmakers down on Hancock Prospecting

The three eldest children of Gina Rinehart, head of the Hancock Prospecting coal and iron ore empire, are suing her in the New South Wales Supreme Court in a bitter dispute over control of the family fortune.

While the sordid details emerging from the proceedings are humiliating enough there may be some serious financial implications for Rinehart – mining’s 4th richest person with a fortune pegged at around $18 billion – as well.

While Rinehart’s business success has been mammoth, her private life has not always been a happy one.

She has not remarried after her second husband died in 1990 and in January Rinehart handed her daughter Ginia (sic) who is 25 years old one of the top jobs in mining, ostensibly because her youngest did not join the others in suing their mother.

An email has now surfaced wherein Rinehart tells Ginia’s siblings Bianca Rinehart, John Hancock and Hope Welker that they have one business day to sign a new agreement limiting access to a trust or face “financial ruin” because the Australian tax office would become aware of their pursuit and slap the family with a huge capital gains bill.

In legal submissions the three elder children characterized Rinehart’s email as a gun held to their heads and “deceptive, manipulative, hopelessly conflicted and disgraceful”.

Court documents also show Ginia’s attempt to mediate between her mother and the three came to nothing. Rinehart and Ginia have been granted a stay by the court and the vesting date of the trust (that would have turned the three elder children into billionaires overnight) has reportedly been pushed out to 2068, when the children would be in their 70s and 80s.

On top of the tax loopholes in family trusts exposed by the Rinehart saga – which have now attracted attention of the country’s lawmakers – it has also emerged that Hancock Prospecting has not submitted annual financial statements for the past two years.

The Sydney Morning Herald also reports that “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.”

While all the scrutiny is definitely not good news for Rinehart, the outlook for the Hancock empire, which Gina is taking into new directions, remains rosy.

Some predict Rinehart, 58, will become the world’s richest person as her coal and iron projects start producing by 2014 and earn her annual profits of as much as $10 billion.

In February Rinehart increased her newspaper and television investments in Australia prompting one observer to comment that Big G (her nickname in the media) is “gonna be the whole shooting match”.

Image is a video capture of Rinehart receiving the 2009 Australia National Business Women’s Awards