Sulawesi Sea Boundaries Still Unsettled After Decades of Talks

UNCLOS sets out rules for delimitation: Article 15 for territorial seas, Article 74 for EEZs, and Article 83 for continental shelves. In the Ambalat and ND6/ND7 context, the continental shelf provisions of Article 83 apply. This article states that overlapping continental shelf claims must be resolved through an agreement that achieves an “equitable” result—not necessarily equidistance, a median line, or equal division.

The term “equitable” leaves wide room for interpretation, which explains why the delimitation process can be prolonged and complex. This is one of the main reasons the Indonesia–Malaysia maritime boundary in the Sulawesi Sea remains unresolved.

Joint Development.
If the boundary remains unsettled, what happens? Article 83 also encourages disputing states to make provisional arrangements for practical cooperation—such as joint development of natural resources—until a final boundary is agreed upon.

In other words, even without a fixed boundary, the two countries can collaborate in utilizing the disputed area. This appears to be the basis for the joint development proposal from President Prabowo and Prime Minister Anwar Ibrahim. However, such an arrangement must be approached with great caution and thorough study.

The Role of Sipadan and Ligitan
Located in the Sulawesi Sea, Sipadan and Ligitan islands were once disputed between Indonesia and Malaysia. Initially unclaimed under international law, both countries sought to establish sovereignty. The ICJ ultimately awarded them to Malaysia.

Some argue that ownership of these islands strengthens Malaysia’s position in the Sulawesi Sea. While there is some truth to this, Malaysia’s 1979 claim already included the islands, meaning their legal status does not fundamentally alter Malaysia’s stance.