Please be informed that Sections 3, 7 and 8 of Article XII of the 1987 Philippine Constitution provide:
"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.
"Section 7. Save in cases of hereditary succession, no private lands shall be transferred or conveyed except to individuals, corporations, or associations qualified to acquire or hold lands of the public domain.
"Section 8. Notwithstanding the provisions of Section 7 of this Article, a natural-born citizen of the Philippines who has lost his Philippine citizenship may be a transferee of private lands, subject to limitations provided by law. (Emphasis supplied)
In the case of Testate Estate of Jose Eugenio Ramirez et al. v. Marcelle D. Vda. De Ramirez et al., GR L-27952, Feb. 15, 1982, through Associate Justice Vicente Abad Santos, the Supreme Court ruled:
"We are of the opinion that the Constitutional provision which enables aliens to acquire private lands does not extend to testamentary succession for otherwise the prohibition will be for naught and meaningless. Any alien would be able to circumvent the prohibition by paying money to a Philippine landowner in exchange for a devise of a piece of land." (Emphasis supplied)
While the afore-quoted decision was promulgated prior to the effectivity of the 1987 Constitution, it must be noted that the provision in the 1987 Constitution limiting an alien's right to own private land in the Philippines through hereditary succession was likewise found in Article XIII, Section 5 of the 1935 Constitution, to wit:
"SEC. 5. Save in cases of hereditary succession, no private agricultural land shall be transferred or assigned except to individuals, corporations, or associations qualified to acquire or hold lands of the public domain in the Philippines."
Pursuant to the aforementioned provisions of the 1987 Philippine Constitution, a foreign national is prohibited from owning private land in the Philippines, except in cases of hereditary succession. This mode of ownership, as clarified by the Supreme Court, is limited to intestate succession.
So if you are not a legal heir of a Filipino but were only constituted as an heir in their will, and the disposition involves private land, it cannot be legally enforced because it is a violation of the Philippine Constitution.
Source: Manila Times