The Philippine Archipelago Doctrine
The territorial limits and boundaries of the Philippines were defined by (1) the Treaty of Paris between the United States and Spain on December 10, 1898; (2) the Treaty of Washington between Spain and the United States on November 7, 1900; and (3) the treaty between Great Britain and the United States on July 2, 1930.
In the Treaty of Paris, Spain transferred its ownership of the Philippines to the United States for $20,000,000, and for the first time the boundaries of the archipelago were then defined.
In the Treaty of November 7, 1900, the United States paid Spain another $100,000 to acquire possession of some small islands in the Sulu archipelago–Cagayan, Sibutu, and the smaller islands around these. These areas were then added to Philippine territory.
Finally, on July 2, 1930, another group of islands were ceded to the Philippine archipelago. These were the Mangsee and Turtle Islands, which had previously been claimed by both Great Britain and the United States.
By the Philippine Constitution of 1973 and by the ratified Constitution of 1987, the Philippines adhered to the Archipelagic Doctrine in defining the boundaries of the country.
Article 1, Section 1, of the 1973 Philippine Constitution, provided that “the national territory comprises the Philippine archipelago with all the islands and waters embraced therein and all the other territories belonging to the Philippines by historic right or legal title, including the territorial sea, the air space, the subsoil, the seabed, the insular shelves, and the other submarine areas over which the Philippines has sovereignty or jurisdiction.”
The same provision of the Philippine Constitution added: “The waters around, between, and connecting the islands of the archipelago, irrespective of their breadth and dimensions, form part of the internal waters of the Philippines.”
Article 1 of the ratified Constitution of 1987 has, more of less, the same provisions.
The Archipelago Doctrine on territorial limits of countries further states that the baselines from which the territorial sea of the archipelago is to be determined consist of the straight lines connection the outermost portions of the islands. Waters within the baselines are Philippine internal waters and waters outside the baselines but within the extent of the international treaty limits, comprise the country’s territorial sea.
This doctrine means, therefore, that our country, with its thousands of islands and many seas, should be considered as a political unit for reasons of history, law, geography, economics, and security. Also, when questions involving territorial conflicts arise, the Philippines has this doctrine to support its claims.













[...] The Philippine archipelago lies between 4º 30′ North and 21º 20′ north latitude and between 116º 55′ East and 126º 36′ east longitude. It is bounded on the north and the west by the South China Sea, on the east by the Pacific Ocean, and on the south by the Celebes Sea and the Sulu Sea. In length, it stretches about 185.15 kilometers (1,150 miles) between the southern tip of Taiwan and the northern tip of Borneo and Indonesia. At its broadest point, it extends about 966 kilometers (600 miles) from east to west. The northernmost island in the country, Y’ami, is 104.65 kilometers (65 miles southeast of Taiwan, while the southernmost island in it, Saluag, is 48.3 kilometers (30 miles) east of Borneo. [...]
[...] of the islands in the Philippine archipelago are characterized by irregular seacoasts, fertile plains and wooded uplands in the [...]
[...] limit the jurisdiction of the state but it embraces those which are inside that jurisdiction. The Philippine Archipelago Doctrine defined the area of responsibility of Philippines during the Spanish regime. It was only during [...]