The United Nations Convention on the Law of the Sea (UNCLOS) was signed in
1982 and came into effect in 1994. The UNCLOS provides a constitution for the oceans
that forms the framework and substance of the rules-based order of maritime
governance, including the allocation of maritime zones to coastal states, as well as
archipelagic states.
As a party to UNCLOS and a law-abiding member of the international community,
the Philippines is bound to perform its obligations in good faith, and thus has the
responsibility to harmonize its laws with the treaty. Therefore, in 2009, it enacted Republic Act No. 9522 to make the baselines of the territorial sea of the Philippine archipelago compliant with UNCLOS. It is from these baselines that the maritime zones seaward from Philippine territory are measured; and it is within these baselines that the Philippines has internal and archipelagic waters.
More infomation: An act declaring the maritime zones under the jurisdiction of the republic of the Philippines ( Senate S.B.No. 1353)
