Finally abolished and its territory annexed to the municipality of Isabela on November 7, 1975, through Presidential Decree No. 840. Rajah Buayan City (1966): Under Republic Act No. 4413, the then-municipality of General Santos in what was then the unified province of Cotabato was to be formally converted into a city named after a historical ruler in Mindanao on January 1, 1966, provided that majority of qualified voters in the municipality vote in favor of cityhood in a plebiscite. In December 1965 the Commission on Elections (COMELEC) proclaimed the cityhood of Rajah Buayan, with 4,422 people voting for and 3,066 voting against. However, two residents of the new city challenged this by arguing in the courts that the number of people who voted in favor of cityhood did not form a majority in light of the fact that there were 15,727 voters in the city. The court issued an injunction on January 4, 1966, restraining city officers from performing any acts authorized by or pursuant to provisions in RA 4413. The Supreme Court unanimously upheld this decision on October 29, 1966, and declared that the city charter was not accepted by majority of voters, thus rendering RA 4413 null and void. The municipality of General Santos would later be converted into a city under the same name in 1968. "League of 16" and legal battles The Supreme Court of the Philippines, by a highly divided vote of 6–5, on November 18, 2008, subsequently upheld with finality on May 6, 2009, declared unconstitutional cityhood laws converting 16 municipalities into cities. The 24-page judgment of Justice Antonio T. Carpio, adjudged that the following Cityhood Laws violate secs. 6 and 10, Article X of the Constitution of the Philippines: RA # 9389 (Baybay in Leyte) RA # 9390 (Bogo in Cebu) RA # 9391 (Catbalogan in Samar) RA # 9392 (Tandag in Surigao del Sur) RA # 9393 (Lamitan in Basilan) RA # 9394 (Borongan in Eastern Samar) RA # 9398 (Tayabas in Quezon) RA # 9404 (Tabuk in Kalinga) RA # 9405 (Bayugan in Agusan del Sur) RA # 9407 (Batac in Ilocos Norte) RA # 9408 (Mati in Davao Oriental) RA # 9409 (Guihulngan in Negros Oriental) RA # 9434 (Cabadbaran in Agusan del Norte) RA # 9435 (El Salvador in Misamis Oriental) RA # 9436 (Carcar in Cebu) RA # 9491 (Naga in Cebu) The Court held that the foregoing