Unregistered land is public land belonging to the State under the Regalian doctrine. Not all public lands or lands of the public domain are alienable and disposable. Under the law, only agricultural lands can be transferred, conveyed or sold to a private individual. There are several ways of acquiring title over alienable and disposable lands, such as Sales Patent, Free Patent, Miscellaneous Patent, CLOA under the agrarian reform program, or through acquisitive prescription under the Civil Code. Some unregistered lands are covered by a tax declaration for real property tax purposes although a tax declaration is not considered as proof of ownership under the law. The declarant may however transfer, sell or convey his rights and interest over an unregistered land to another person.