Iron Ore Price, page-1812

er6n,
From the ATO web page, one example......

"A wealthy individual was sentenced to eight-and-a-half years imprisonment for money laundering and avoiding millions in tax. He was investigated after declaring minimal income to the ATO while living a luxurious lifestyle.
The individual created several offshore companies to which he sold his shares well below the true market value. By doing so, he artificially reduced his tax liabilities in Australia, while keeping control of the shares."

Does that not sound similar to the 'hub' in Singapore?

If the purpose of the offshore companies is just to reduce tax, it is currently illegal.

If BHP and RIO sold IO to a company in Singapore 'cheaply', then that company sold the IO to China at the real price, and this company just happened to be owned by BHP/RIO then they are in a lot of trouble. I suggest you just don't understand tax law in this regard.