The Department of State announced the outer limits of the US continental shelf in areas beyond 200 nautical miles from the coast. Continental shelf beyond 200 nautical miles is known as the extended continental shelf or ECS.

The US ECS is approximately 1 million square kilometers (more than 386,000 square miles) spread across seven regions, and supports many resources (e.g., coral, crabs) and vital habitats for marine life.

Since 2003, US government agencies, including NOAA, have been engaged in gathering and analyzing data to determine the outer limits of the US extended continental shelf. The announcement is the product of that two-decade collaboration among the Department of State, NOAA, and the US Geological Survey.