Who really owns the Caspian Sea?

The Caspian Sea has long been a source of contention among Iran, Russia, Azerbaijan, Kazakhstan, and Turkmenistan. The five countries border the Caspian, but it is neither a conventional sea nor a simple international lake. Instead, they have established a unique legal framework governing various aspects of the sea. In 2018, the five presidents signed the Convention on the Legal Status of the Caspian Sea, which established territorial waters and fishing zones, but did not divide the entire sea into equal shares for each country.

This convention aimed to clarify the shared use of the Caspian, rather than assigning ownership percentages to the respective nations. Iran has historically claimed 50% of the Caspian, but this assertion has not been internationally recognized. Instead, the treaty emphasizes common usage and delineates distinct zones for navigation, fishing, security, and resources.

While offshore oil and gas rights can be divided between neighboring states, the seabed remains subject to bilateral agreements. Iran's southern boundaries with Turkmenistan and Azerbaijan remain a politically sensitive issue, as the 2018 convention prohibits foreign military presence in the Caspian. Ukraine's alleged attack on an Iranian vessel in the Caspian demonstrates the geopolitical tension surrounding the region.

Iran, the only signatory yet to ratify the convention, is concerned about maintaining the Caspian as a non-military area. The country's focus on hydrocarbon potential, particularly offshore oil and gas resources, has made deepwater development challenging due to sanctions. However, Iran's hydrocarbon potential remains uncertain and undeveloped compared to its more accessible Persian Gulf and onshore fields.

Ultimately, no single nation owns or controls the Caspian Sea, and ownership percentages are no longer the primary concern. The key issues now involve resource management, maritime boundaries, and preventing external military interference.