By Marcus Bennett

The Permanent Court of Arbitration in The Hague issued its award on July 12, 2016. The Hague-based tribunal ruled largely in favor of the Philippines, invalidating core elements of China's expansive South China Sea claims.

Ten years later, the Philippines is marking the anniversary. The commemorations, reported by Radio Free Asia, underscore how the tribunal's decision continues to shape maritime law debates across Southeast Asia.

How did the case reach arbitration?

The arbitration began in January 2013. The Philippines filed its notification and statement of claim under Annex VII of the United Nations Convention on the Law of the Sea, a 1982 treaty that both Manila and Beijing have ratified. China initially declined to participate in the proceedings but later filed a position paper. Five judges formed the Arbitral Tribunal, led by President Thomas A. Mensah of Ghana.

The panel addressed three groups of questions. The first group concerned the legal status of maritime features in the Spratly Islands. The second examined whether China's nine-dash line had any legal basis under UNCLOS. The third looked at whether Chinese activities in waters the Philippines claimed had violated the convention.

What did the tribunal decide?

On the Spratly features, the tribunal found that no feature in the group generated an exclusive economic zone. The panel characterized Mischief Reef, Second Thomas Shoal, and Reed Bank as low-tide elevations or submerged banks. Only where low-tide features sit within 200 nautical miles of a coastal state's baseline can they help draw the line, and here the math did not favor China's expansive claims.

On Itu Aba, called Taiping Island by Taiwan, the tribunal ruled it was a "rock" under Article 121(3) of UNCLOS. Rocks, by that article, cannot sustain human habitation or economic life of their own, and they generate no exclusive economic zone or continental shelf. The panel rejected Taipei's argument that Itu Aba qualified as a full island.

On the nine-dash line, the panel concluded that China had no legal basis for historic rights within sea areas falling inside the Philippines' exclusive economic zone. The tribunal said the nine-dash line conflicted with UNCLOS and had been superseded by the convention's EEZ regime.

On Chinese activities, the panel found multiple breaches. Chinese fishing by state vessels in Philippine waters violated the Philippines' sovereign rights. China's land reclamation and construction at Mischief Reef breached duties to protect the marine environment. The tribunal also concluded that Chinese authorities had failed to prevent traditional fishing by Chinese nationals at Scarborough Shoal.

How did China and the Philippines respond?

China rejected the award within days of its release. The Ministry of Foreign Affairs called the ruling "null and void" and accused the tribunal of overreach. Beijing said it would neither recognize nor comply with the decision. China has maintained that position for ten years.

The Philippines under President Rodrigo Duterte set the legal victory aside after July 2016. Manila chose to pursue bilateral talks with Beijing, a shift that critics inside and outside the Philippines called a surrender of the award's gains. The two sides signed documents that contained no reference to the arbitral decision.

The administration of President Ferdinand R. Marcos Jr. has changed course. Since taking office in 2022, Manila has filed more than 200 diplomatic protests against Chinese actions, most tied to incidents at Second Thomas Shoal. Philippine officials now invoke the 2016 award in nearly every public statement on the South China Sea.

Why does the anniversary matter in 2026?

The 10-year mark arrives with regional tensions still elevated. Chinese coast guard vessels have continued to confront Philippine resupply missions and fishing boats. Incidents recorded through 2024 and 2025 drew statements of concern from Washington, Tokyo, Canberra, and Brussels.

Maritime law scholars treat the award as the most comprehensive arbitral application of UNCLOS in the modern era. No other tribunal has addressed so many convention articles in a single dispute. Lawyers advising governments in other maritime cases now cite the 2016 ruling as a baseline reference.

The United States, Japan, Australia, and the European Union have endorsed the award's findings. Their backing strengthens the Philippines' diplomatic position. None has committed to military action to enforce the ruling, however.

For Filipino fishermen and workers at Reed Bank and around Scarborough Shoal, the gap between law and practice remains wide. The 2016 award recognized the Philippines' rights in plain terms. Ten years on, those rights are still asserted mostly in diplomatic notes and news conferences.

The anniversary is therefore more than ceremonial. It is a reminder that international law can deliver a clean win, and that enforcing that win is a separate, harder project.