by the Straits Settlements Light-Houses Ordinance 1912, the lighthouse was vested in Singapore. After 1912, the duties levied on ships passing through the Singapore Strait were abolished; instead, the costs of the lighthouse were shared by the neighbouring states. In 1946, following World War II, Singapore became a separate Crown Colony. The other Straits Settlements, Malacca and Penang, joined the Malay states (including Johor) to form the Malayan Union. The latter became the Federation of Malaya in 1948, and the Federation of Malaysia in 1963. On 17 June 1953, the Colonial Secretary of Singapore wrote to the British Adviser to the Sultan of Johor to clarify the status of Pedra Branca. He noted that the rock was outside the limits ceded by Sultan Hussein Shah and the Temenggung with the island of Singapore under the Treaty of Friendship and Alliance of 2 August 1824 they had entered into with the East India Company. However, the Colonial Government had been maintaining the lighthouse built on it, and "[t]his by international usage no doubt confers some rights and obligations on the Colony". He therefore asked if "there is any document showing a lease or grant of the rock or whether it has been ceded by the Government of the State of Johore or in any other way disposed of". The Acting State Secretary of Johor replied on 21 September that "the Johore Government does not claim ownership of Pedra Branca". This correspondence indicated that as of 1953 Johor understood it did not have sovereignty over Pedra Branca, which had therefore vested in the United Kingdom. The Colony of Singapore became a self-governing state in 1959 and left the British Empire to join the Federation of Malaysia in 1963. Two years later, in 1965, Singapore became a fully independent republic. In 1959, in an official publication regarding meteorological information collected on Pedra Branca, Malaya listed Horsburgh Lighthouse as a "Singapore" station together with the Sultan Shoal and Raffles Lighthouses. The lighthouse on Pedra Branca was described in the same way in a joint Malaysian and Singaporean publication in 1966, the year after Singapore left the Federation. In 1967, when the two countries began reporting meteorological information separately, Malaysia ceased referring to Horsburgh Lighthouse. In maps published by the Malayan and Malaysian Surveyor General and Director of General Mapping in 1962, 1965, 1970, 1974 and 1975, the island was indicated with the word "(SINGAPORE)"