Malaysia–Thailand joint development area
The Malaysia–Thailand Joint Development Area is a 7,250 km square area in the Gulf of Thailand which was created as an interim measure to exploit the natural resources in the seabed or continental shelf claimed by the two countries and to share the proceeds equally. The arrangement does not extinguish the legal right to claims by both countries over the area.
Source: Wikipedia — Malaysia–Thailand joint development area (CC BY-SA 4.0)