Selling leases to state-owned subsurface rights that grant the lessee the right to explore for oil is not the same thing as selling the oil.  The lessees only convert the oil to their ownership when they bring it to the surface, and that is also only contingent upon the lessee paying the required royalties and taxes, as well as rentals, unit payments, and so on.  We've spoiled the majors by allowing them to extend their leases and units almost in perpetuity, but that is not also not the same thing as selling them unfettered rights to the oil. It's Alaska's oil.