Who said anything about splitting the profits? Lynas has pricing...

Who said anything about splitting the profits? Lynas has pricing power and can take most of the profit for itself. It's also not clear that Lynas couldn't charge less for the ore than its own cost to extract from its own deposits.

I think the better argument against the proposal is the idea that Lynas needs to fine-tune its processes for quality based on specific types of input, and doing that from a uniform deposit that it controls would be much easier than taking in many different types of ores from different sources.

The other point is demand is not strong enough to exhaust their own reserves for decades, so there is no need for more ore yet.