""Secondly, if the ATO got wind of copper getting sold for less,...

""Secondly, if the ATO got wind of copper getting sold for less, then being divvied up overseas, someone would end up in jail. It called transfer pricing and a big fat no-no."""

The transfer pricing issues (for tax) arise only when the buyer is effectively controls the company either through 50+ ownership or Board control, or is a 'related party' linked to the parent.
This would not have been so when the off-take was signed.

Are you saying that control may be possible...soon. In that case i agree there would be tp risks if new contracts are made for delivery cu at discounted rates? ie shifting profits overseas.

But there are other consequences of effective controls... like divies, Board overhaul, drilling over returns to sh, etc...which ato would not be in interested in.