Hancock Prospecting, the private company of billionaire Gina Rinehart, has partly lost a decade-long legal battle with Wright Prospecting over royalties, but will retain ownership of a major iron-ore hub in Australia.

The Supreme Court of Western Australia delivered its judgment rejecting Hancock’s argument that Wright Prospecting had no royalty rights over some iron ore tenements that include the massive Hope Downs mine that it shares with Rio Tinto Group. Wright Prospecting had a right to some royalties, the court found.

“Any amounts payable regarding royalties and interest to Wright Prospecting or Rhodes is a shared responsibility with our partner Rio Tinto, who have a further royalty contribution in this regard,” Hancock Prospecting said in a statement following the judgment.

Rio Tinto did not’t immediately respond to a request for comment.

The complex legal case was brought more than a decade ago by Wright Prospecting, which argued it was entitled to royalties from the Hopes Down project and questioned Hancock’s ownership rights. The court ruled Wright had no rights to ownership of a tenement under question.

Hope Downs and the tenements are one of the largest iron-ore hubs in the Pilbara region of Western Australia, and income from it catapulted Rinehart to billionaire status as China’s industrialization led to a boom in demand for the steelmaking ingredient.

Wright Prospecting is a private company owned by the descendants of prospector Peter Wright, who was a business partner of Rinehart’s father, Lang Hancock. The two men formed a venture staking claims over the iron-ore-rich Pilbara region many decades ago.

A spokesperson from Wright Prospecting said that it welcomes the decision and it will review the lengthy judgment in detail before determining the next steps.

The descendants of Wright argued under that partnership, both Wright Prospecting and Hancock Prospecting were entitled to a equal share in those assets. DFD Rhodes, another company owned by descendants of another prospector Don Rhodes, also made a claim that it was entitled to royalties.

During the trial, more than 4 000 documents were tendered into evidence.

“At the heart of the issues raised by the parties to the proceedings were a number of formal agreements made decades ago between men who were friends or colleagues who for some years engaged in harmonious and co-operative arrangements to explore, discover and prospect for iron ore in the East Pilbara,” Western Australia Supreme Court Justice Jennifer Smith said in a summary judgment on april 15.

Rinehart’s own children John Hancock and Bianca Rinehart were also parties in proceedings seeking a share of ownership. Their claim was rejected. The decision is likely to be subject to appeal.