There is a contention between the Federal Government and the Sarawak Government over the legitimacy of the Sarawak (Alteration of Boundaries) Order in Council (OIC) 1954 and its relation to the Territorial Sea Act 2012 (TSA 2012). The Sarawak OIC 1954, enacted under the Colonial Boundaries Act 1895, extended Sarawak's boundaries to cover the “continental shelf” and allowing resource exploration. The historical and legal implications of the OIC for Sarawak's maritime boundary and its alignment with international law, particularly the 1958 Geneva Convention on the Continental Shelf and the United Nations Convention on the Law of the Sea (UNCLOS) 1982 remain unclear. This paper aims to provide an initial understanding of the Sarawak OIC 1954 by examining its history and archives to clarify the complexities of this important document. It offers insights based on archived UK documents from 1945 to 1974, exploring the historical legitimacy and motivations behind the OICs and their role in delineating maritime boundaries adjacent to Sarawak.