1987 Constitution of the Philippines
Section 3. Lands of the public domain are classified into agricultural, forest or timber, mineral lands and national parks. Agricultural lands of the public domain may be further classified by law according to the uses to which they may be devoted. Alienable lands of the public domain shall be limited to agricultural lands. Private corporations or associations may not hold such alienable lands of the public domain except by lease, for a period not exceeding twenty-five years, renewable for not more than twenty-five years, and not to exceed one thousand hectares in area. Citizens of the Philippines may lease not more than five hundred hectares, or acquire not more than twelve hectares thereof, by purchase, homestead, or grant.
Taking into account the requirements of conservation, ecology, and development, and subject to the requirements of agrarian reform, the Congress shall determine, by law, the size of lands of the public domain which may be acquired, developed, held, or leased and the conditions therefor.