A Key Piece in the Clayton Valley Lithium Patchwork, page-6

it's just an article relevant to SOC's lithium aspirations, take from it what you will.

The biggest issue, and one that most players in the basin conveniently leave out, is that the rights to extract the ground water are all tied up by Albemarle.

That is the reason they didn't bother staking claims over the whole valley.... they don't need to.

Even if one of these new players were to find a good source of brine, they wont be allowed to extract it.

"Prior to development of the brine resource by Albemarle’s predecessors, a salt flat and brine pool existed in the north part of the basin, but groundwater pumping has eliminated the surface brine pool."

That is the thing with aquifers, unlike rocks they don't respect claim boundaries.