Gina Rinehart’s company will have to pay hundreds of millions of dollars to a rival business after securing the rights but losing some royalties on a major mine in a landmark court case.

The more than 15-year-long Western Australian supreme court case pitted the extended families of Rinehart’s father and his business partner against each other, while tying up mining company Rio Tinto and a string of others.

Who won and who lost? Will Rinehart still be the richest person in Australia?

Here’s what you need to know.

What’s the case about?

The case involved disputes over the ownership of mining plots in Western Australia’s Pilbara region and over the royalty income from mines developed on the plots.

Business partners Peter Wright and Lang Hancock, Gina Rinehart’s father and the founder of Hancock Prospecting, made a series of claims over mining plots from the 1950s onwards. They often traded their ownership of the land for separate rights to royalties from mines developed on the land, typically splitting royalties 50-50.

In 1984 and 1985, after a long campaign, the partners gained access to a set of tenements later called Hope Downs and the East Angelas. Wright died in 1985 and Hancock died in 1992.

In 2005, Hancock Prospecting, now led by Gina Rinehart, agreed with a Rio Tinto subsidiary to develop a co-owned mining project on the Hope Downs tenements. The project later began mining the East Angelas tenements. The profits went to Rio Tinto and Hancock Prospecting.

Who are Wright Prospecting?

Wright Prospecting launched the case in 2010, claiming it had the right to half of Hancock’s royalties on any mines in the Hope Downs tenements. In 2012, it claimed a 50% stake in the East Angelas, which would entitle it to a share of profits from mines built on those plots, on top of royalties.

Wright Prospecting has since 2012 been jointly owned by Peter Wright’s daughter, Angela Bennett, and two of his granddaughters, Leonie Baldock and Alexandra Burt. The company has made billions from the royalties paid by mines developed on its land claims, making all three billionaires.

What did the Wrights win?

In Wednesday’s judgment, Wright Prospecting won its claim to half of past and future royalties for the mines in the Hope Downs and East Angelas, which have been paid by Rio Tinto to Hancock Prospecting.

Hancock Prospecting has estimated that will amount to $14m a year. Hancock-Rio mines have been profitable on the tenements for 16 years, which would imply over $220m in back pay to the Wrights. Rio Tinto is expected to pay more on top of that, with the exact amounts to be determined in future hearings.

The Wrights lost their claim to own the East Angelas tenements, so will not get the profits, which are separate from the royalties.

What did Gina Rinehart win?

Rinehart’s company, Hancock Prospecting, won its claim to owning the Hope Downs and East Angelas jointly with Rio Tinto.

It defeated the Wrights’ claim to the East Angelas and their profits. It also defeated Rinehart’s children’s claims to the land, which were thrown out after the judge found they relied on Lang Hancock’s fraudulent corporate manoeuvring.

Hancock Prospecting also won its claim that Rio Tinto should contribute to paying the owed royalties, interest and legal costs.

What did Gina Rinehart’s children and others win?

Rinehart’s children won a partial confirmation of their claims to a greater stake in their mother’s business.

Justice Jennifer Smith determined a plan agreed by Gina Rinehart and her father in 1988 would have left 51% of the company’s shares to Rinehart and the other 49% to her children. Rinehart now controls 76.55% of the company and the children control 23.45%.

The children have alleged Gina Rinehart had fraudulently rearranged the company’s affairs after Lang Hancock’s death, which Hancock Prospecting has denied. Smith did not make a ruling, finding the children’s claims were irrelevant to the Hope Downs case and should be determined in an ongoing private arbitration.

Another party claiming a win was the family business of Don Rhodes, a former business partner of Hancock and Wright who helped them unlock iron ore tenements in the Pilbara.

DFD Rhodes won its claim against Hancock Prospecting, to past and future royalties from Hancock’s 50% share of the revenues from mines on some of the tenements.

Hancock Prospecting estimated it would have to pay $4m a year.

Will Gina Rinehart still be Australia’s richest person?

Wednesday’s judgment alone is not likely to knock Rinehart from her position as Australia’s richest person.

Rinehart’s wealth has been valued at about $40bn in recent years, largely from her 76.55% controlling stake of Hancock Prospecting and its mines. Hancock Prospecting made $4.5bn in profit in 2024-25 and $7.8bn the year before.

Peter Strachan, an independent mining analyst, said Rinehart and Hancock Prospecting would be able to handle the costs even if forced to pay hundreds of millions to the Wrights and DFD Rhodes.

“It’s not hugely material to her wealth, but as the Rhodes side was quoted as saying, she was a ‘formidable opponent’, so I don’t think she’d be taking it lightly,” Strachan said.

However, the judgment cleared the way for an ongoing private arbitration to make rulings over Rinehart’s children’s long-running claim for a bigger stake of Hancock Prospecting.

If the arbitration found in favour of the children, Rinehart’s share of the company and her wealth could be reduced dramatically, Strachan said.

“That would be more material,” he said. “Since it hasn’t been resolved, there’s a question mark over it but I think there’s a lot of water to flow under the bridge before we get a final view.”