Notes on the South China Sea case: islands, rocks, Article 121, New Zealand islands, and marine scientific research
Historic rights and the South China Sea case
The speaker introduces the South China Sea dispute by focusing on historic rights to islands and rocks as a central issue, specifically China's "nine-dash-line" claim, which broadly encompasses much of the South China Sea. The tribunal’s key move was to treat the complex, "Jade-like question" of historic rights—meaning those based on long-standing claims or traditional fishing practices—as something that the creation of the exclusive economic zone (EEZ) under the United Nations Convention on the Law of the Sea (UNCLOS) could effectively override, at least in the contested area. The tribunal meticulously examined China’s historical practice of fishing and resource exploitation within the claimed area. It found that while such activities occurred, they did not amount to a consistent state practice that other states had expressly or tacitly accepted, which is a key requirement for the formation of a contrary rule of customary international law that could establish historic rights. Therefore, there was no "acquiescence" by other states in a practice that deviated from the UNCLOS framework. In short, the tribunal concluded that there were no historic rights of the kind China was asserting based on the nine-dash-line in the South China Sea that could supersede the modern maritime zones defined by UNCLOS. This sets the stage for understanding how the tribunal approached the broader question of maritime zones and sovereignty in a region with overlapping claims, emphasizing that UNCLOS provides a comprehensive legal regime designed to govern maritime entitlements. The lesson is that historic practice alone, especially when contested or not universally accepted, cannot overcome the modern, internationally agreed framework of UNCLOS when it is designed to create EEZs that extend beyond traditional high-seas usage. Questions about historic rights were thus intrinsically tied to whether any feature in the South China Sea could generate a maritime zone that would affect the eventual delimitation and jurisdiction of the tribunal itself. This also meant that claims based on historical maps, like the nine-dash line, were effectively deemed incompatible with UNCLOS.
Article 121 and the three classifications for features in the South China Sea
A central part of the tribunal’s analysis involved Article 121 of UNCLOS, particularly the definitions and distinctions it draws between islands, rocks, and low-tide elevations (LTEs). Article 121 is structured into three paragraphs, each specifying how a feature is treated for maritime zone generation. An island, as defined in Article 121(1), is a naturally formed area of land surrounded by water and above water at high tide. According to Article 121(2), a feature that qualifies as an island can generate a full suite of maritime zones: a territorial sea (up to 12 nautical miles), a contiguous zone (up to 24 nautical miles), an exclusive economic zone (EEZ, up to 200 nautical miles), and a continental shelf. The crucial third paragraph, Article 121(3), acts as a limiting clause, stating: "Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf." In effect, a feature can generate either a full 200 nautical mile EEZ (and potentially a continental shelf beyond that) if it unequivocally qualifies as an island and meets the criteria of Article 121(3), or it can only generate a 12 nautical mile territorial sea if it is a rock or an LTE that cannot sustain habitation or economic life. The tribunal thus had the critical task of classifying each feature in the Spratly group as an island, rock, or LTE and then, for those above water at high tide, determining whether it could sustain human habitation or economic life of its own. The analysis turns on a combination of the explicit text of UNCLOS, the context in which it was drafted, and the negotiating history of Article 121. The tribunal paid close attention to why negotiators chose to avoid "windfalls" for very small features, meaning they wanted to prevent tiny, insignificant landmasses from generating vast maritime zones. The drafters were conscious that uninhabitable rocks should not automatically grant a state broad jurisdictional claims over immense ocean areas. The result of this rigorous classification exercise in the tribunal's mapping was striking: there were effectively no features in the South China Sea that qualified as "islands" under their interpretation of Article 121(1) and (3) as capable of generating an EEZ or continental shelf. This outcome means that, under the tribunal's interpretation, a feature would generally not generate an EEZ or continental shelf unless it could demonstrate the capacity to sustain genuine human habitation or an economic life of its own, independent of external support. The tribunal also highlighted that the determination of whether a feature is an island can have significant effects on jurisdiction, since Article 298 provides voluntary exclusions from disputes concerning maritime delimitation for states that have made such declarations. If a feature were deemed an island, potentially leading to a maritime boundary dispute, the tribunal might lack jurisdiction over certain issues tied to maritime delimitation, reinforcing why the tribunal approached the issue with extreme caution and a preference for avoiding island status whenever possible for features in this contested area.
The concept of habitation and economic life: factors and thresholds
To define whether a feature can generate an EEZ, the tribunal meticulously broke down the notion of "habitation" and "economic life of its own" into specific, strict criteria. First, habitation requires not just a single person, a temporary research team, or a military garrison, but rather a stable, enduring community that considers the feature their permanent home. This implies a sustained presence over generations. At a minimum, true habitation requires reliable and self-sufficient access to fundamental necessities such as food (e.g., through agriculture or sustainable fishing from the feature itself), drinkable water (e.g., from natural springs or dependable rainfall collection), and adequate shelter, thereby establishing a long-term, self-sufficient ability to sustain life on the feature without constant external resupply. Second, an economic life of its own implies that the feature sustains a community through indigenous economic activities that organically tie inhabitants to the site, rather than being merely an outpost for resource extraction. Mere extraction of resources (like guano, as historically seen in some Spratly features, or oil/gas from adjacent waters) is deemed insufficient to create an economic life in the sense of Article 121(3) because it establishes a circular argument: using the potential EEZ resources to justify the economic life of the feature would defeat the purpose of the limiting clause. The tribunal emphasized that a feature’s economic life is typically connected to a self-sufficient community living on or near the feature and deriving its livelihood directly and primarily from the feature itself. Third, the tribunal considered the crucial role of external supply and the overarching requirement that any habitation be truly self-sustaining; consistent and significant reliance on supplies, infrastructure, or personnel from outside the feature generally undermines the argument for genuine habitation or an independent economic life. Historical evidence of past habitation is highly relevant; if a feature has never supported a stable, self-sufficient community in the past, it provides strong evidence that it is unlikely to do so naturally in the future without substantial artificial intervention. The tribunal thus set a remarkably high bar for a feature to be treated as an island capable of generating an EEZ. In the context of Itu Aba (Taiping Island), despite its relatively larger size, the presence of a runway, institutional housing, farms for livestock and vegetables, and a freshwater well, the tribunal concluded that Itu Aba was too small to naturally sustain a sizable and stable population without significant external aid. Furthermore, its documented habitation history, which included temporary presences such as military garrisons or past seasonal fishermen, did not demonstrate a durable, self-sustaining community, independent of external support, over a meaningful period. The discussion also recognized that a feature could theoretically be part of a chain of islands, yet the chain alone is not enough to sustain habitation unless there is evidence of a self-contained, stable community with the inherent capacity to live without persistent external support from mainland territories or other substantially larger islands.
Itu Aba (Taiping Island): facts, reasoning, and implications
Itu Aba (Taiping Island) is the largest naturally occurring feature in the Spratly Islands, with significant built infrastructure, including a 1,200-meter runway, a wharf, a hospital, a temple, and housing, and is currently under the administrative control of Taiwan. The tribunal meticulously assessed Itu Aba’s physical characteristics, noting its natural freshwater supply, indigenous vegetation, and its relatively larger landmass compared to other features in the Spratlys. However, despite historical evidence of a notable presence of fishermen and workers—including those involved in guano mining in the 1920s–1930s—and intermittent habitation by military personnel and researchers, the tribunal ultimately ruled that these activities and presences do not amount to a stable, self-sustaining community necessary to classify the feature as an island under Article 121(3) of UNCLOS. The historical presence of temporary workers, often engaged in extractive activity or military duties, did not satisfy the rigorous criteria for "habitation" or "economic life of its own" in a durable, self-sufficient sense. The tribunal found that the ability of the feature to sustain a population was not inherent or independent, but rather heavily reliant on external resupply and a subsidized economy. Consequently, the tribunal concluded that Itu Aba could not generate an EEZ or a continental shelf, only a 12-nautical-mile territorial sea. This outcome matters significantly because if Itu Aba had qualified as an island with an EEZ, it would have created complex overlapping claims and directly affected potential maritime delimitation lines between claimant states, particularly China and the Philippines. Since it did not qualify, the jurisdictional calculations could proceed differently, allowing for a clearer application of UNCLOS principles without the added complexity of a feature-generated EEZ. The Itu Aba decision stands as a prime illustration of how the tribunal interpreted paragraph three of Article 121 by applying a rigorous, context-driven test for habitation and economic life, rather than simply relying on the surface appearance of infrastructure or the mere existence of some economic activity on the feature.
The New Zealand context: testing South China Sea criteria on NZ islands
The lecture turns to New Zealand’s existing EEZ and a practical exercise applying the South China Sea criteria to some of New Zealand’s offshore island chains. The Kermadec Islands (including Raoul Island and others) sit far to the north of the main islands, with Raoul Island itself being about square kilometers. The other features collectively total under square kilometers but are spread over roughly kilometers. Raoul Island has a documented history of sustained settlement by the Bell family (1878–1913/35 years) and has hosted a continuously operating meteorological station since 1937, along with coast watchers during World War II. The Chatham Islands are located about kilometers east of Christchurch and cover nearly square kilometers, with a population historically around people and continuous habitation since at least , including ongoing fishing and farming as primary economic activities. The Auckland Islands (main island around square kilometers) and Campbell Islands (around square kilometers) are larger subantarctic features with documented short-lived settlements (e.g., whaling stations, castaways) and coast watcher presences. The Antipodes Islands ( square kilometers) are south of the Stewart Island group and have a history of sealing activities and very limited, highly temporary habitation. The Bounty Islands ( barren granite outcrops spanning about five nautical miles) are largely uninhabitable but important for seabirds; the Snares with its main island at about square kilometers similarly have significant seabird populations but little to no potential for sustained human habitation. In the exercise, students debated whether each feature would qualify as an island capable of generating an EEZ under the rigorous South China Sea framework. The results varied considerably: The Chatham Islands and Campbell Islands were almost universally treated as islands due to their size, documented stable populations, and self-sustaining economic activities. Raoul Island was heavily debated due to its smaller size but long history of meteorological station personnel. Auckland Island was frequently viewed as not an island under the tribunal's test due to the harsh subantarctic conditions and lack of evidence of a truly stable, self-sustaining human habitation. The Antipodes were often treated as not an island due to their remoteness, extreme environmental constraints, and only temporary historical uses. The Bounty and Snares were generally not considered islands under the strict interpretation of Article 121(3). The exercise highlighted how NZ’s long-standing EEZ claim, which has been deposited with the United Nations under UNCLOS and is widely supported by international fisheries treaties and state practice, would be vulnerable to a different and more restrictive interpretation of Article 121 if challenged in an arbitration. However, in practice, the broad acceptance through state practice and acquiescence by other nations has strongly supported NZ’s existing EEZ claim. The discussion also touched on the notion of state practice and customary international law as potential reinforcing factors; while customary law is not likely to establish the NZ EEZ as a rigid, independently derived rule, it may inform how international tribunals interpret Article 121 in future disputes, especially where decades of unchallenged state practice exist.
Windfalls and small features around the world: the Okino Torishima example
The session underscores the inherent risk that some features—especially very small rocks or "rock-like" features, often with substantial artificial enhancements—could be argued to generate disproportionately large EEZs purely as "windfalls." A prime example is Okino Torishima (also known as Parece Vela), a remote Japanese atoll. This feature consists of only a few tiny rock outcrops (reportedly varying in size but some no larger than a "double bed") that barely remain above water at high tide. Japan has undertaken extensive measures, including the construction of concrete and steel reinforcements, to prevent erosion and ensure these rocks remain above sea level. Japan claims this feature is an island capable of generating a full EEZ, extending its maritime jurisdiction significantly to the south of its mainland. This expansive claim, based on such a diminutive and arguably uninhabitable feature, has prompted strong challenges from neighboring states, most notably China, which argues that Okino Torishima is merely a "rock" under Article 121(3) and thus should only generate a 12-nautical-mile territorial sea. The tribunal’s rigorous approach to windfalls, emphasizing that the mere appearance of an island or artificial preservation is not enough, but that the feature must inherently meet genuine habitation and life-sustaining criteria, helps explain why some states push back vehemently against expansive EEZ claims derived from tiny, naturally uninhabitable features. The Okino Torishima dispute is an ongoing illustration of the tensions surrounding the interpretation and application of Article 121(3).
Marine scientific research (MSR): Article 246 and related issues
A bonus topic in the lecture addresses marine scientific research (MSR) and the complex related questions about jurisdiction and consent within maritime zones. Article
of UNCLOS states that coastal states have the exclusive right and jurisdiction to regulate, authorize, and conduct MSR in their EEZ and on their continental shelf. In principle, coastal states are generally expected to grant consent for MSR conducted by other states or international organizations, especially when the research is for peaceful purposes and aims to increase scientific knowledge for the benefit of all humanity. However, consent can legitimately be withheld if the MSR is of direct significance for the exploration and exploitation of natural resources of the EEZ and continental shelf (e.g., resource surveys), or if it involves drilling, explosives, or is likely to interfere with coastal state economic activities. The discussion explains that there has long been a significant debate among states and scholars about what precisely constitutes MSR, with inherent tensions between the interests of freedom of scientific inquiry (often advocated by major maritime and scientific powers) and the sovereign resource exploitation rights and security concerns of coastal states. The talk also notes that the MSR definitions were never fully settled during UNCLOS negotiations, leading to ambiguities. Some scholars distinguish between "pure research" (fundamental scientific inquiry) and "applied research" (research with practical, often commercial, applications). However, much applied MSR (e.g., bathymetric surveys, seismic surveys directly tied to resource assessment) often falls into the category of resource exploration rather than pure MSR, significantly complicating the consent framework under Article 246. The United States’ longstanding stance on MSR and extended continental shelf issues—illustrated by recent examples of US vessels claiming MSR rights over the Arctic’s extended continental shelf without requiring explicit consent from potentially affected states—highlights how MSR intersects with broader jurisdictional issues and the evolving balance between freedom of scientific inquiry and coastal state sovereignty. The speaker points out that MSR is often conducted with sophisticated technologies, including manned and unmanned submersibles (e.g., AUVs, ROVs), autonomous floats (e.g., Argo floats), satellite remote sensing, boreholes, and various sampling methods (e.g., coring, dredging). These technologies vastly expand our understanding of oceanography, climate change, marine biodiversity, and deep-sea resources, underscoring why the MSR regime remains a significant and often contested area for the law of the sea practice.
Broader implications: dispute settlement, state practice, and geopolitics
The South China Sea case has been a singularly rich source of legal and geopolitical insight into the efficacy and limitations of international law. The tribunal’s assumption of jurisdiction hinged on its determination of whether any feature was an island capable of generating an EEZ, as certain disputes related to maritime delimitation with 'islands' were potentially excluded from its compulsory jurisdiction under Article 298. Its striking finding that there were effectively no such "islands" in the disputed area simplified the South China Sea situation from a purely legal perspective by removing a significant jurisdictional obstacle. However, China’s decision to emphatically not participate in the proceedings, to reject the tribunal’s authority, and to declare the ruling null and void, significantly affected the dispute’s dynamics. The case starkly illustrates that compulsory dispute settlement under UNCLOS, while legally binding, ultimately relies on the political will of states for their consent, participation, and compliance. Powerful states have sometimes resisted or outright rejected international tribunal rulings when they perceive them as infringing on their national interests or sovereignty. The panel’s conclusions about historic rights and the broader implications of China's failure to accept the tribunal’s jurisdiction contribute to ongoing debates about the legitimacy, effectiveness, and enforceability of compulsory dispute settlement mechanisms in international law, particularly when major powers question the authority of international courts. The discussion emphasizes that the law of the sea does not operate in a vacuum but within a broader geopolitical environment, where strategic national and regional interests, shifts in power dynamics, and the specific historical practices of states deeply shape outcomes. It highlights that multilateral treaties like UNCLOS create robust institutions and detailed legal procedures but do not automatically guarantee universal compliance, especially when perceived national interests appear to override international norms and legal obligations. The lecture connects these points to ongoing sovereignty disputes around the world (e.g., the Senkaku/Diaoyu Islands dispute between Japan, Korea, and China in the East China Sea, or similar disputes in the Arctic) and notes that public perception and domestic political realities can heavily influence whether states choose to pursue adjudication, negotiation, or other diplomatic channels. Finally, the lecturer points toward future developments, including potential Bilateral and Joint (BB&J) arrangements which might offer practical solutions for resource management and cooperation in disputed areas. The overall message stresses that while dispute settlement is a vital tool for the peaceful resolution of international disputes, it is not a panacea and must be understood alongside diplomacy, power politics, and the ongoing development and pursuit of customary international law at sea.
Concluding reflections: key takeaways for exams
Historic rights in the South China Sea: The tribunal found that China's claims to historic rights based on the "nine-dash-line" were largely displaced by the precise, spatially defined zones established under UNCLOS. The tribunal held that no enduring historic rights existed in the area because there was no sufficient evidence of a consistent, long-standing contrary practice acquiesced to by other states that could supersede the UNCLOS framework.
Article (3) distinctions: This critical article differentiates islands from less significant features like rocks and low-tide elevations (LTEs). Rocks which cannot sustain human habitation or economic life of their own are explicitly excluded from generating an EEZ or continental shelf, leading to only a 12-nautical-mile territorial sea. This provision creates a strong incentive for tribunals to avoid "windfall" designations for small or artificially sustained features.
Habitation and economic life criteria: The tribunal’s demanding emphasis on a stable, self-sustaining, and long-term viable human habitation and an independent economic life sets a high bar for a feature to generate large maritime zones. The case of Itu Aba illustrated how even a feature with significant infrastructure and some historical human presence may fail this threshold due to its size, reliance on external support, and lack of a truly durable, self-sufficient community.
NZ island exercise implications: The practical exercise applying the South China Sea framework to New Zealand's islands revealed how such a stringent interpretation of Article 121(3) could yield different outcomes for features in a distant archipelago, potentially challenging long-standing EEZ claims. This highlights the ongoing role of established state practice, international acquiescence, and the potential for new disputes about whether to classify a feature as a full island or merely a rock (or LTE).
Windfall claims risks: Claims based on tiny rocks or artificially stabilized features, as exemplified by Okino Torishima, have the potential to generate disproportionately large EEZs. Such "windfall" claims pose risks to the equitable distribution of maritime zones and frequently provoke widespread objections and challenges from neighboring states concerned about expansive jurisdictional assertions.
Marine scientific research (MSR) complexity: MSR is a complex area governed by Article where consent, the specific purposes of the research, and its potential direct significance to resource exploitation create a nuanced balance. There’s a continuous tension between the principle of freedom of scientific inquiry and coastal state sovereignty over their EEZ and continental shelf, often complicated by unclear definitions of "pure" versus "applied" research.
Broader geopolitical context: The South China Sea case remains a critical reference point for understanding the intricacies of international jurisdiction, the interplay between international law and geopolitics, and the inherent limits of compulsory dispute settlement when major powers do not participate. It also powerfully illustrates the importance of continued state practice in shaping the evolving legal landscape, especially as states respond to rising geopolitical tensions and changing power dynamics in global ocean governance.