July 2026 marks the tenth anniversary of the South China Sea arbitration award issued by an arbitral tribunal constituted under Annex VII to the 1982 United Nations Convention on Law of the Sea (UNCLOS). The 2016 ruling, initiated by the Philippines against China, rejected the legal basis for China’s “nine-dash line” claims. China’s position on the arbitration is the “Three Nos”: no acceptance, no participation and no recognition.
Although many states welcomed and supported the arbitration’s ruling and considered it a landmark decision with binding force, the ruling is not uncontested. There are scholars within the international law community, such as Stefan Talmon, a professor of international law at University of Bonn, who argue that the case was “decided wrongly”, that the tribunal lacked jurisdiction, that some of the Philippines’ claims were inadmissible, and that procedural errors occurred during the proceedings. The tribunal’s decision to classify Itu Aba (Taiping Island) as a “rock” was also highly contentious, with legal scholars such as Myron Nordquist and William Phalen arguing that the tribunal erred in the interpretation and application of UNCLOS.
Regardless of these scholarly debates, the Philippines certainly considers that it won a great legal victory against China and maintains that any outcome of the settlement of the South China Sea dispute must be based on the arbitration award. The wider and practical impact of the arbitration on the situation in the South China Sea, however, has been rather mixed.
A decade after the arbitration ruling, tensions between China and the Philippines persist, with episodic serious clashes. Yet amid this complex geopolitical landscape, one lesson has become increasingly clear: legal principles alone cannot guarantee stability, nor can military posturing create lasting security. While international law remains important, the political will and diplomatic skills to manage the differences also matter as much. The future of the South China Sea will depend on whether regional states can expand practical maritime cooperation while managing their differences responsibly.
The general impression that the ruling invalidated China’s maritime claims in the South China Sea is an oversimplification. Whether one considers the merits of China’s objection, the fact is that the tribunal did not resolve questions of sovereignty over rocks and reefs. There is also no mechanism for enforcing its findings. As a result, political realities continue to shape developments at sea.
China’s rejection of the award has remained unchanged over the past decade. Its construction of maritime infrastructure, expansion of coast guard operations and growing naval capabilities have reinforced its presence across much of the South China Sea. Meanwhile, Southeast Asian claimant states have strengthened their own maritime capabilities, with some seeking greater support from external partners such as the US, Japan, India, Australia and the EU. This dynamic has contributed to an increasingly crowded and securitised maritime environment.
Yet focusing exclusively on strategic competition risks overlooking the importance of maintaining practical cooperation. International experience suggests that countries do not always need to settle territorial and/or maritime disputes before working together on shared interests, and this applies even in cases involving states with adversarial relations. Practical cooperative and confidence-building measures often create the political conditions necessary for reducing tensions over time.
The South China Sea presents numerous opportunities for such cooperation. Marine biodiversity is under severe pressure from overfishing, coral reef degradation and climate change. Illegal, unreported and unregulated fishing threatens food security across Southeast Asia. Maritime accidents involving fishing vessels, coast guards and commercial shipping require improved communication mechanisms to prevent unnecessary escalation. Natural disasters regularly demand coordinated humanitarian assistance and disaster relief operations.
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ASEAN has long promoted the principle of managing disputes peacefully while encouraging practical cooperation. Although negotiations on a substantive Code of Conduct between ASEAN and China have progressed slowly, the process itself reflects a shared recognition that rules and communication channels are preferable to unmanaged competition. A meaningful Code of Conduct will require compromise from all parties and credible implementation mechanisms, and it remains one of the most important diplomatic initiatives for regional stability and regional maritime order.
Economic cooperation also deserves renewed emphasis. The South China Sea remains one of the world’s busiest maritime trade routes, carrying a substantial portion of global commerce. Ensuring freedom of navigation, protecting undersea communication cables and maintaining safe shipping lanes are shared interests that transcend geopolitical competition. Stable maritime governance benefits both claimant and non-claimant states alike.
Moreover, promising blue economy initiatives such as eco-aquaculture, blue carbon trading, sustainable marine tourism, smart ports and logistics systems can also be introduced to promote shared prosperity, sustainability and practical cooperation among all stakeholders.
Cooperation certainly should not come at the expense of international law. Respect for UNCLOS remains essential as the foundation of the global maritime order. While governments may continue to disagree over specific legal interpretations or the status of the 2016 arbitration, adherence to internationally accepted rules provides a common language for managing disputes peacefully. A rules-based maritime order does not eliminate political disagreements, but it offers predictable mechanisms for addressing them.
The South China Sea is a shared maritime space that connects economies, supports livelihoods, and sustains millions of people across Asia. Building habits of cooperation in areas where interests converge does not diminish legal principles or questions of national sovereignty. Rather, it provides a practical foundation for managing differences responsibly and preventing disputes from undermining regional stability.
A decade after the 2016 arbitration, one important lesson is that lasting peace and a sustainable regional order require more than legal rulings or military deterrence alone. They require sustained diplomacy, mutual restraint, effective crisis management and a willingness to pursue cooperation where common interests exist. The future of the South China Sea should therefore not be defined solely by competing claims, but also by the shared responsibility of all parties to maintain it as a space of peace, connectivity and common development.
