The South China Sea Arbitration (Philippines v China)

The South China Sea Arbitration (Philippines v China) PCA Case No. 2013-19 

Judges 

The Arbitral Tribunal consisted of five members: 

1. Judge Thomas A. Mensah (Presiding Arbitrator) – Ghana 
2. Judge Jean-Pierre Cot – France 
3. Judge Stanislaw Pawlak – Poland 
4. Professor Alfred H.A. Soons – Netherlands 
5. Judge Rüdiger Wolfrum – Germany 

The Tribunal operated in compliance with Article 9 of Annex VII of UNCLOS, which mandates that before making an award, an arbitral tribunal must confirm that it has jurisdiction and that the claims are well-founded in both fact and law.1 

Representatives 

Republic of the Philippines 

1. Agent 

— Mr. Florin T. Hilbay, Solicitor General of the Philippines, replacing Solicitor General Francis H. Jardeleza, as of 2 March 2015 

2. Counsel and Advocates 

— Mr. Paul S. Reichler 

— Mr. Lawrence H. Martin, Foley Hoag LLP, Washington, DC 

— Professor Bernard H. Oxman, University of Miami School of Law, Miami — Professor Philippe Sands QC, Matrix Chambers, London 

— Professor Alan Boyle, Essex Court Chambers, London 

People’s Republic of China 

No agents or representatives appointed 

Introduction 

The South China Sea Arbitration was a historic international arbitration involving territorial disputes and marine rights in the South China Sea between China and the Philippines.2In accordance with Annex VII of the 1982 United Nations Convention on the Law of the Sea (UNCLOS), the Philippines started the proceedings on January 22, 2013.3 After diplomatic talks failed to settle disagreements over China’s broad maritime claims and activity in regions that the Philippines also claimed, arbitration was necessary.4 The Philippines sought a peaceful legal resolution through international arbitration because of the significant disparity in the two states’ economic and military might.5 The legal status of marine features in the South China Sea, the legitimacy of China’s “nine-dash line” claim, and the consistency of Chinese actions with UNCLOS were among the significant issues at stake in the conflict. Due to the South China Sea’s geopolitical and economic significance, it carries an estimated US$3 trillion in yearly global trade and contains considerable fisheries and hydrocarbon resources to which the issue garnered a lot of interest from around the world.6 

Court Hearing 

The Permanent Court of Arbitration (PCA) served as the Tribunal’s Registry during the proceedings, which took place at the Peace Palace in The Hague, Netherlands.7 There were two stages to the arbitration. Held from July 7th to 13th, 2015, the Hearing on Jurisdiction and Admissibility reviewed the admissibility of the Philippines’ allegations as well as the Tribunal’s jurisdiction to consider the case.8 The substantive legal problems presented by the Philippines were the subject of the Hearing on the Merits, which took place from November 24 to 30, 2015.9 

China declined to formally participate in the proceedings, claiming that any final award would be “null and void” and that the Tribunal lacked authority.10 Article 9 of Annex VII of UNCLOS, however, states that the lack of a party does not stop the procedures from going on. Throughout the arbitration procedure, the Tribunal invited views and provided China with all written submissions, transcripts, and procedural papers to guarantee procedural fairness. 

Parts of the hearings were attended by a number of observer states, including Australia, Indonesia, Japan, Malaysia, Singapore, Thailand, and Vietnam. 

Facts of the Case 

China’s broad maritime claims and its actions in parts of the South China Sea that the Philippines claims gave rise to the conflict. China claimed “historic rights” over a sizable maritime region bounded by the “nine-dash line,” which is depicted on official Chinese maps. These claims substantially overlapped with maritime regions that, according to UNCLOS, belong within the Philippines’ Exclusive Economic Zone (EEZ). The Philippines has asked for clarification on the legal status of a number of marine features, such as Spratly Islands features and Scarborough Shoal. The Tribunal was requested to decide if these features qualified as low-tide elevations producing no maritime entitlements, rocks entitled only to a 12-nautical-mile territorial sea, or islands capable of generating a 200-nautical-mile EEZ. 

Additionally, the Philippines claimed that China had illegally interfered with its fishing and petroleum exploration operations, especially in the vicinity of Reed Bank. Additionally, China was charged with building man-made islands on many coral reefs and carrying out massive land reclamation programs. 

Evidence that was presented to the Tribunal showed that Chinese operations had seriously harmed the environment. Under the cover of Chinese government vessels, Chinese fishermen were discovered to have used destructive fishing techniques to capture endangered marine species, such as coral, gigantic clams, and sea turtles. Coral reef habitats were severely damaged by extensive dredging and land reclamation operations. 

Legal Issues 

The Tribunal took into account a number of significant legal issues: 

1. whether UNCLOS was compatible with China’s claims to historical rights within the “nine-dash line.” 
2. Whether UNCLOS must be the exclusive basis for determining maritime rights in the South China Sea. 
3. Whether specific marine features qualified as low-tide hills, rocks, or islands under UNCLOS Article 121. 
4. Whether China’s interference with fishing and petroleum exploration operations in the Philippines’ EEZ breached the country’s sovereign rights. 
5. whether China violated its commitments to safeguard and preserve the marine environment under Part XII of UNCLOS 
6. Whether China breached its duties under the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS) regarding navigational safety. 

Court’s Decision 

On July 12, 2016, the Tribunal issued its Final Award, which was heavily in favour of the Philippines. 

The Tribunal determined that the UNCLOS-established framework for maritime entitlement was irreconcilable with China’s claims to historic rights within the “nine-dash line.” It came to the conclusion that UNCLOS fully regulates maritime entitlements and provides no legal foundation for claims that go beyond those bounds. 

The Tribunal additionally decided that none of the Spratly Islands’ characteristics qualified as fully entitled islands that could provide an EEZ. According to UNCLOS Article 121(3), some features, such as Johnson Reef, Cuarteron Reef, Fiery Cross Reef, and Gaven Reef North, were only entitled to a territorial sea since they were categorised as “rocks.” Mischief Reef and Subi Reef, among other features, were categorised as low-tide elevations that do not produce separate marine zones. According to the Tribunal, China’s development of artificial islands and interference with Philippine activities constituted infringement of the Philippines’sovereign rights under UNCLOS because Mischief Reef was found to be within the Philippines’ Exclusive Economic Zone. 

It was also determined that China’s extensive land reclamation and construction operations had seriously and permanently harmed the ecosystem. The Tribunal came to the conclusion that China had not done enough to stop its fishermen from harming coral reef ecosystems and exploiting endangered marine animals. Furthermore, the Tribunal determined that Chinese law enforcement vessels had violated COLREGS’s requirements for maritime safety and collision prevention by acting dangerously during interactions with Philippine vessels. 

Critical Analysis 

A critical examination of the South China Sea Arbitration (Philippines v. China) finds a nuanced balance between the Award’s noteworthy legal and procedural issues and its significance as a seminal interpretation of UNCLOS. Despite being widely acknowledged as a significant clarification of maritime entitlements, the 2016 ruling is still hotly contested in international legal study because of issues with jurisdiction, interpretation, and efficacy. 

Jurisdiction and the Tribunal’s handling of sovereignty questions are major points of contention. The Award’s opponents contend that the Tribunal successfully sidestepped the actual argument, which was more about sovereignty over South China Sea maritime features than it was about UNCLOS maritime entitlements.11 The Tribunal is reported to have avoided issues that fall outside the mandatory dispute resolution procedures by framing the dispute as one involving the interpretation of UNCLOS articles rather than sovereignty over island groups.12 Furthermore, detractors contend that China’s stance was reframed in a disjointed way, emphasising specific characteristics rather than a cohesive territorial claim over island groups, so permitting jurisdiction where it might have otherwise been excluded.13 

The dispute over the Tribunal’s interpretation of UNCLOS Article 121 is closely related to this. In order to differentiate between islands and rocks, the Tribunal took a restrictive stance, adding qualitative factors such as the genuine ability for human habitation and economic existence.14 Opponents contend that the Tribunal essentially reduced the range of what could be considered an island and that these criteria are not clearly stated in the Convention. Critics point out that similar marine features elsewhere in the world have been treated as whole islands capable of producing EEZs, and this has been especially contested in relation to features like Itu Aba.15 Additionally, some academics contend that by considering paragraph 3 (rocks) as a presumption rather than a narrow exemption, the Tribunal inverted the interpretive structure of Article 121 and shifted the burden of proof in a manner that the language does not explicitly support.16 

The Tribunal’s handling of historic rights is another important topic of discussion. According to the Award, claims to historic rights within EEZs and continental shelves are effectively excluded and superseded by UNCLOS.17 Critics counter that this view is too rigid. In some situations, historic rights may exist independently of treaty regimes under general international law. Jurisprudence like the Eritrea/Yemen arbitration is frequently cited as proof that historic usage can have legal significance even in the presence of contemporary maritime frameworks.18 This viewpoint criticises the Tribunal for taking a limited “treaty-first” stance that did not adequately address the coexistence of UNCLOS and customary international law. 

Due to China’s non-participation, the Award has also been scrutinised procedurally.19 Despite the Tribunal’s legal right to proceed in default, some observers contend that this increased the Tribunal’s obligation to uphold stringent evidentiary standards. It has been questioned whether the burden of proof was effectively reduced because the Tribunal relied on independently sourced historical information and expert testimony that the Philippines had not fully developed in its submissions.20 Furthermore, the way expert testimony is handled has been critiqued for restricting cross-examination chances, which lowers procedural transparency in technically complicated matters, especially when it comes to environmental and navigational safety conclusions. 

The effect of the Award on third-party rights is the subject of yet another significant criticism. Despite their non-participation in the proceedings, other claimant governments including Vietnam, Malaysia, and Taiwan may have their interests impacted by the Tribunal’s conclusions about the legal status of marine features.21 The Monetary Gold principle, which forbids international tribunals from determining the rights of absent third parties where such rights constitute the “very subject matter” of the case, is raised by this.22 Particularly contentious is the categorisation of features like Itu Aba as “rocks” rather than islands since it directly challenges Taiwan’s long-held stance without providing it with a chance to argue before the Tribunal.23 

The Award is nonetheless very important as an illustration of legal “lawfare” and the calculated exploitation of international dispute resolution procedures by smaller powers, despite these objections. The Philippines’ effective use of mandatory arbitration shows how international law can be applied to contest power imbalances and bring significant territorial issues to the courts.24 Despite China’s rejection of the Award as “null and void,” it has had a significant impact on norms.25In order to promote a rules-based maritime order, many nations, including the United States, Japan, and Australia, still rely on the Award as an authoritative interpretation of UNCLOS.26 

However, its usefulness is still restricted. China’s ongoing presence and militarisation of South China Sea features highlights the disconnect between legal determination and geopolitical reality.27 The lack of enforcement measures means that compliance is solely dependent on political will. Because of this, the Award is frequently referred to as a “legal victory without enforcement,” highlighting the limitations of international adjudication in high-stakes geopolitical issues as well as the power of international legal reasoning. 

Conclusion 

A great many individuals consider the South China Sea Arbitration to be a seminal case in the evolution of maritime law and international dispute resolution. Modern interpretation of UNCLOS has been greatly influenced by the Tribunal’s Award, especially with regard to marine entitlements, historic rights, environmental obligations, and navigational safety. The Award continues to be a significant legal authority for the peaceful use of the seas and the boundaries of historical maritime claims under international law, despite ongoing enforcement issues. The case illustrates the advantages and disadvantages of using international adjudication to settle intricate geopolitical conflicts. 

REFERENCES 

ANH, N. T. L. (2016). The South China Sea award: Legal implications for Vietnam. Contemporary Southeast Asia, 38(3), 369–374. http://www.jstor.org/stable/24916761 Campbell, C., & Salidjanova, N. (2016). South China Sea arbitration ruling: What happened 

and what’s next. United States–China Economic and Security Review Commission. https://www.uscc.gov/sites/default/files/Research/Issue%20Brief_South%20China%2 0Sea%20Arbitration%20Ruling%20What%20Happened%20and%20What%27s%20 Next071216.pdf 

Catalyst International. (2025). The South China Sea dispute: A nexus of claims, law, and 

geopolitical strategy. https://catalyst-international.org/2025/08/13/the-south-china-sea-dispute-a-nexus-of-c laims-law-and-geopolitical-strategy/ 

Kwiatkowska, B. (2000). The Eritrea/Yemen arbitration: Landmark progress in the 

acquisition of territorial sovereignty and equitable maritime boundary delimitation. Durham University, IBRU Centre for Borders Research. https://www.durham.ac.uk/media/durham-university/research-/research-centres/ibru-c entre-for-borders-research/maps-and-databases/publications-database/boundary-amp-s ecurity-bulletins/bsb8-1_kwiatkowska.pdf 

Mollengarden, Z., & Zamir, N. (2021). The monetary Gold principle: Back to basics. 

American Journal of International Law, 115(1), 41–77. https://doi.org/10.1017/ajil.2020.86 

National Institute for South China Sea Studies. (2020). A legal critique of the award of the 

arbitral tribunal in the matter of the South China Sea arbitration. In S. Lee & H. E. Lee (Eds.), Asian Yearbook of International Law, Volume 24 (2018) (pp. 151–293). Brill. https://doi.org/10.1163/j.ctv1sr6j7f.11 

Permanent Court of Arbitration. (2015). In the matter of the South China Sea arbitration (The

Republic of the Philippines v. The People’s Republic of China): Award on jurisdiction and admissibility (PCA Case No. 2013-19). https://legal.un.org/riaa/cases/vol_XXXIII/1-152.pdf 

Romaniuk, S. N., et al. (2025). China’s strategic ambitions, assertiveness and escalation in the 

South China Sea. Eurasia Review. https://www.eurasiareview.com/24112025-chinas-strategic-ambitions-assertiveness-an d-escalation-in-the-south-china-sea-analysis/ 

Talmon, S. (2016). The South China Sea arbitration: Observations on the award on 

jurisdiction and admissibility. Chinese Journal of International Law, 15(2), 309–391. https://doi.org/10.1093/chinesejil/jmw025 

Wiegand, K. E. (2025). International law and conflict disputes: The case of the South China 

Sea. Perry World House, University of Pennsylvania. https://perryworldhouse.upenn.edu/news-and-insight/international-law-and-conflict-di sputes-the-case-of-the-south-china-sea/ 

Wisnugroho, A. M. (2024). International law and the challenges in implementing UNCLOS: 

South China Sea arbitration. https://moderndiplomacy.eu/2024/07/17/international-law-and-the-challenges-in-impl ementing-unclos-south-china-sea-arbitration/

1 Permanent Court of Arbitration. (2015). In the matter of the South China Sea arbitration (The Republic of the Philippines v. The People’s Republic of China): Award on jurisdiction and admissibility (PCA Case No. 2013-19). https://legal.un.org/riaa/cases/vol_XXXIII/1-152.pdf

2ibid

3ibid 

4 Catalyst International. (2025). The South China Sea dispute: A nexus of claims, law, and geopolitical strategy. https://catalyst-international.org/2025/08/13/the-south-china-sea-dispute-a-nexus-of-claims-law-and-geopolitical -strategy/ 

5 Campbell, C. & Salidjanova, N. (2016). South China Sea arbitration ruling: What happened and what’s next. United States–China Economic and Security Review Commission. 

https://www.uscc.gov/sites/default/files/Research/Issue%20Brief_South%20China%20Sea%20Arbitration%20R uling%20What%20Happened%20and%20What%27s%20Next071216.pdf 

6 Catalyst International. (2025, August 13). The South China Sea dispute: A nexus of claims, law, and geopolitical strategy. 

https://catalyst-international.org/2025/08/13/the-south-china-sea-dispute-a-nexus-of-claims-law-and-geopolitical -strategy/ 

7 Permanent Court of Arbitration. (2015). In the matter of the South China Sea arbitration (The Republic of the Philippines v. The People’s Republic of China): Award on jurisdiction and admissibility (PCA Case No. 2013-19). https://legal.un.org/riaa/cases/vol_XXXIII/1-152.pdf 

8Ibid 

9Ibid 

10 Ibid

11 National Institute for South China Sea Studies. (2020). A legal critique of the award of the arbitral tribunal in the matter of the South China Sea arbitration. In S. Lee & H. E. Lee (Eds.), Asian Yearbook of International Law, Volume 24 (2018) (pp. 151–293). Brill. https://doi.org/10.1163/j.ctv1sr6j7f.11

12 Talmon, S. (2016). The South China Sea arbitration: Observations on the award on jurisdiction and admissibility. Chinese Journal of International Law, 15(2), 309–391. https://doi.org/10.1093/chinesejil/jmw025 13 ibid 

14 National Institute for South China Sea Studies. (2020). A legal critique of the award of the arbitral tribunal in the matter of the South China Sea arbitration. In S. Lee & H. E. Lee (Eds.), Asian Yearbook of International Law, Volume 24 (2018) (pp. 151–293). Brill. https://doi.org/10.1163/j.ctv1sr6j7f.11

15 ibid 

16 ibid 

17 ibid 

18 Kwiatkowska, B. (2000). THE ERITREA/YEMEN ARBITRATION: Landmark Progress In The Acquisition Of Territorial Sovereignty and Equitable Maritime Boundary Delimitation. Durham University, IBRU Centre for Borders Research. https://www.durham.ac.uk/media/durham-university/research-/research-centres/ibru-centre-for-borders-research/ maps-and-databases/publications-database/boundary-amp-security-bulletins/bsb8-1_kwiatkowska.pdf

19 National Institute for South China Sea Studies. (2020). A legal critique of the award of the arbitral tribunal in the matter of the South China Sea arbitration. In S. Lee & H. E. Lee (Eds.), Asian Yearbook of International Law, Volume 24 (2018) (pp. 151–293). Brill. https://doi.org/10.1163/j.ctv1sr6j7f.11 

20 Wisnugroho, A.M. (2024). International law and the challenges in implementing UNCLOS: South China Sea arbitration. https://moderndiplomacy.eu/2024/07/17/international-law-and-the-challenges-in-implementing-unclos-south-chi na-sea-arbitration/

21 ANH, N. T. L. (2016). The South China Sea Award: Legal Implications for Vietnam. Contemporary Southeast Asia, 38(3), 369–374. http://www.jstor.org/stable/24916761 

22 Mollengarden, Z., & Zamir, N. (2021). The Monetary Gold Principle: Back to Basics. American Journal of International Law, 115(1), 41–77. doi:10.1017/ajil.2020.86 

23 National Institute for South China Sea Studies. (2020). A legal critique of the award of the arbitral tribunal in the matter of the South China Sea arbitration. In S. Lee & H. E. Lee (Eds.), Asian Yearbook of International Law, Volume 24 (2018) (pp. 151–293). Brill. https://doi.org/10.1163/j.ctv1sr6j7f.11 

24 Wiegand, K. E. (2025). International law and conflict disputes: The case of the South China Sea. Perry World House, University of Pennsylvania. 

https://perryworldhouse.upenn.edu/news-and-insight/international-law-and-conflict-disputes-the-case-of-the-sou th-china-sea/ 

25 ibid 

26 ibid 

27 Romaniuk, S. N. et al. (2025). China’s strategic ambitions, assertiveness and escalation in the South China Sea. Eurasia Review. https://www.eurasiareview.com/24112025-chinas-strategic-ambitions-assertiveness-and-escalation-in-the-south china-sea-analysis/