Before extraction of offshore freshened groundwater (OFG) begins, ownership must first be determined in order to confirm the right to access, possess and distribute of the resource.  Since the geological formations sheltering OFG extend beyond the coastline, the UN Convention on the Law of Sea, which has been ratified by most countries in the world, will apply, and it provides that the nation having rights to the continental shelf where the OFG is located will have sovereign rights to the resource.  However, political boundaries do not often respect geologic formations, and some deposits of OFG will straddle national boundaries.  The Law of the Sea Convention is silent on transboundary resources, so policymakers must look to other legal principles that address governance of natural resources in order to develop a governance regime.  This presentation will summarize the applicable international law principles and will provide guidance on how transboundary OFG may be governed.