The 2016 South China Sea Award and the Future of a Legally Binding Code of Conduct

A Philippine Marine speedboat patrols off the coast of Thitu Island while a China Coast Guard vessel nears it, in the disputed South China Sea, on May 3, 2026 | Photo by Daniel Ceng / Anadolu via AFP

In this article published by Fulcrum, Joanne Lin and Huynh Trung Dung examine the effects of the continuing legal divergence of recognizing the 2016 South China Sea Arbitral Award on ASEAN and China’s pursuit of a legally binding Code of Conduct.

For more than a decade, key ASEAN Member States (AMS) have regarded the formulation of a legally binding Code of Conduct in the South China Sea (COC) as a key objective in its approach to managing tensions in the South China Sea (SCS). Since negotiations formally began in 2018, the pursuit of a legally binding instrument has become an important benchmark for success. It reflects the broader expectation that clearer rules and obligations under the COC could promote greater predictability, reduce the risks of incidents and reinforce a rules-based regional order.

This ambition gained renewed momentum under Indonesia’s 2023 ASEAN Chairmanship, when ASEAN and China agreed to try to conclude negotiations within three years. It has been reinforced by the current Chair, given the Philippines’ call to complete the COC by end-2026. As negotiations enter what could be a decisive phase, that the Code should be legally binding remains one of ASEAN’s foremost objectives.

Yet, a decade after the 2016 South China Sea Arbitral Award, the legal landscape surrounding the COC has become increasingly complex. On the Award’s recent tenth anniversary, China reaffirmed that it rejects the ruling as “illegal, null and void”, maintaining that disputes over territorial issues and maritime delimitation cannot be subject to “imposed solutions” and arguing that the arbitration violated fundamental principles of international law, including state consent, and the 1982 UN Convention on the Law of the Sea (UNCLOS). However, the Award serves as an important legal reference point for some claimant states in advancing their maritime claims under UNCLOS.

This divergence raises the question at the heart of the COC negotiations: If the parties continue to differ over the interpretation and application of UNCLOS, how can a future legally binding COC effectively operate in practice?