Philippine nationality law is currently based upon the principles of jus sanguinis and therefore descent from a parent who is a citizen/national of the Republic of the Philippines is the primary method of acquiring Philippine citizenship. Birth in the Philippines to foreign parents does not in itself confer Philippine citizenship, although RA9139, the Administrative Naturalization Law of 2000, does provide a path for administrative naturalization of certain aliens born on Philippine soil (Jus soli). Together, some of these recent immigrants have intermarried with the indigenous Filipinos, as well as with the previous immigrant groups, giving rise to Filipinos of mixed racial and/or ethnic origins also known as mestizos.