The owner of real property generally has exclusive rights to the soil and minerals underneath the land. Significant limitations on subsurface rights have to be disclosed in the title deed at the time of acquisition. If no restrictions are indicated, the buyer can expect to exercise full rights to the property. It is important to note, however, that in some states, the owner of land is not automatically assumed to also be the owner of the subsurface. That is, land ownership may be separated. In many areas, subsurface rights can be extremely valuable because of the existence of oil, natural gas, and minerals, and those must be acquired separately.