Constitutional Court Rejects Lawsuit to Rename 'South China Sea' to 'North Natuna Sea'

The Chief Justice of the Constitutional Court, Suhartoyo, stated that the Court cannot accept the judicial review of Law Number 2_5 of 2002 concerning the Formation of Riau Islands Province (UU Kepri). Decision Number 277/PUU-XXIV/2026 was delivered in the Constitutional Court’s Plenary Session on Friday, 28 August 2026.

In the Court’s legal considerations regarding the petition filed by Zico Leonardo and two other petitioners, Vice Chairman of the Constitutional Court Saldi Isra stated that regarding the legal standing of the petitioners, the Court did not find a clear description of constitutional loss resulting from the enforcement of the norm being tested. Furthermore, regarding the testing of laws concerning regional interests, the Court has established a precedent regarding the parties entitled to file such petitions, namely regional heads together with the Regional House of Representatives (DPRD) as decided through a Plenary Session.

As established in Court Decisions Number 87/2015, 137/2015, 31/2025, and 95/2025, since the petitioners are not part of the regional government, there is no factual or potential constitutional loss violated by them. “Based on the facts and legal considerations of the petition, the Court has no doubt in declaring that the Petitioners of Application Number 277/PUU-XXIV/2026 do not have the legal standing to file the application,” said Saldi.

Previously, the petitioners sought the constitutional review of Article 5 paragraph (1) letter a of Law 25/2002. They claimed to suffer potential and actual harm due to the enforcement of the norm in question, as the Indonesian Government has officially established the nomenclature “North Natuna Sea” to refer to the waters north of the Natuna Islands, which are part of Indonesia’s EEZ and border the South China Sea and Vietnam’s EEZ south of the Ca Mau Peninsula.

This designation was incorporated into the updated Indonesian national map and officially communicated to the public as a step to assert sovereignty. The petitioners explained that the naming of the “North Natuna Sea” is strictly distinguished from the “Natuna Sea,” so that juridically and geographically, Indonesia recognises two names for two different parts of the waters previously referred to as the “South China Sea”: the Natuna Sea (to the south) and the North Natuna Sea.

The People’s Republic of China (PRC) has long claimed almost the entire South China Sea based on the nine-dash line. The PRC bases its claim on historical grounds that it asserts have existed since the 2nd century BC. This claim significantly overlaps with Indonesia’s EEZ in the North Natuna Sea region.