South China Sea Islands

The delimitation of the maritime boundaries in the South China Sea should be linked to the question whether the (land reclamations on the) reefs in the South China Sea are islands or rocks or Low Tide Elevations (LTEs).

Article 121 UNCLOS has the following three paragraphs:

1. An island is a naturally formed area of land, surrounded by water, which is above water at high tide.

2. Except as provided for in paragraph 3, the territorial sea, the contiguous zone, the exclusive economic zone and the continental shelf of an island are determined in accordance with the provisions of this Convention applicable to other land territory.

3. Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf.


This article includes two categories of islands: (1) the islands that are capable of sustaining human habitation or economic life of their own, and therefore, just like other land territory, can have territorial sea, contiguous zone, EEZ, and continental shelf; and (2) the islands that are incapable of sustaining human habitation or economic life of their own, and therefore are treated as “rocks.”

The islands belonging to the second category have no right to generate an EEZ or continental shelf, but they can have a territorial sea and contiguous zone. The land feature that is able to sustain human habitation or has an economic life of its own and can generate an EEZ or continental shelf has been called a “full-fledged island” in China’s Shifting Sands in the Spratlys (ASIL Insight of July 15, 2015) by J. Ashley Roach.


Artificial islands are not entitled to a territorial sea, contiguous zone, Exclusive Economic Zone (EEZ) or continental shelf. Nevertheless it remains possible that the underlying maritime features can be classified as Article 121 (1) islands if they meet all of the applicable criteria and are not properly classified as rocks or LTEs.


As far as overlapping territorial claims in the South China Sea are concerned, "coastal states have a compelling motive to classify their sovereign claims as 'islands' rather than rocks in order to increase the area over which they could exercise some form of national jurisdiction. Similarly, states are inclined to assert that the sovereign claims of their competitors are characterized not as islands, but mere 'rocks'."

In addition to substantial natural resources, the South China Sea is of paramount strategic significance to the Asian security paradigm and to global stability. Freedom of navigation through the South China Sea is a particular concern for the great naval powers, including the United States and Japan. While China has historically preferred to handle all disputes bilaterally, the resumption of negotiations between Beijing and ASEAN still holds promise for reinvigorating a multilateral framework toward greater cooperation and conflict resolution.

At the moment four areas are involved in maritime boundary disputes in the South China Sea: the Spratly Islands, Scarborough Reef/Shoal, the Paracel Islands and Natuna Island.

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Spratly Islands

China (Nan-sha Ch’un-tao) - Malaysia (Kepulauan Spratly) - Phillipines (Pangkat Islang Kalayaan) - Taiwan (Nansha Qundao) - Vietnam (Quan Dao Truong Sa)

China claims about 90% of the South China Sea, including the archipelago of islands, reefs and atolls known as the Spratlys (red line at the picture: 'nine-dash line'). Vietnam has the second most expansive claim. It asserts sovereignty over the entirety of the Paracel and Spratly Islands, the most significant land features in the South China Sea. Malaysia claims sovereignty over a cluster of features in the Spratlys close to its coast, and Brunei claims two Spratly features. The Philippines claim the western section of the Spratlys (theKalayaan Island Group). Manila also asserts that: “China’s claims to sovereign rights and jurisdiction, and to ‘historic rights’, with respect to the maritime areas of the South China Sea encompassed by the so-called ‘nine-dash line’ are contrary to the convention and without lawful effect to the extent that they exceed the geographic and substantive limits of China’s maritime entitlements under UNCLOS.”

The government of the Philippines argues in the South China Sea arbitration case that all features in the Spratly archipelago are incapable of sustaining human habitation or economic life of their own. In the arbitration case, the Philippines admits that three of the seven reefs meet the definition of an island, that is, they are naturally formed areas of land surrounded by and above water at high tide. If so, they are capable of a claim to sovereignty and to maritime zones of their own. However, the islands on the three reefs occupied by China are very small and contain little vegetation. Therefore, the Philippines maintains that they should be classified as “rocks which cannot sustain human habitation or economic life of their own”. If so, they would be entitled to a 12 nautical mile (nm) territorial sea, but not to an exclusive economic zone (EEZ) or continental shelf of their own. With regard to the remaining four reefs occupied by China, the Philippines maintains that they are not islands under UNCLOS as they are submerged at high tide. Therefore, they are not subject to a claim of sovereignty and are not entitled to any maritime zones of their own.

Even the largest feature in the Spratlys, that is, Taiping Island (Itu Aba), is a “rock” and accordingly, cannot generate maritime entitlement to a 200 nautical mile Exclusive Economic Zone (EEZ) under UNCLOS.Is Taiping Island an “island” or a “rock” under the UNCLOS? Is Taiping Island capable of sustaining human habitation or economic life of its own? Is Taiping Island entitled to generate a 200-nm EEZ or a continental shelf? It is Taiwan’s position that Taiping Island is “a full-fledged island” and therefore can generate a 200-nm EEZ in accordance with Article 121 of UNCLOS.

In the South China Sea Arbitration Award (12 July 2016) the Philippines expresses concern that if any of the Spratly Islands were found to be fully entitled islands and China remained determined to avoid any form of legally binding adjudication or arbitration of the boundary, the dispute could be “frozen”. By contrast, the Philippines argues, a determination that the features were only rocks would reduce the incentive to “flex muscles and demonstrate sovereignty over minuscule features” that generate a maximum entitlement of 12 nautical miles, and thus contribute to the “legal order and the maintenance of peace in the South China Sea (paragraph 421.). According to the Philippines, none of the features in the Spratly Islands is capable, based on its own natural elements, of sustaining both human habitation and economic life of their own (paragraph 426.).

More info in Max Planck Encyclopedia of Public International Law [MPEPIL] on Spratly Islands by Michael Strupp

Scarborough Reef/Shoal

China (Huangyan Island) - Philippines (Panatag Shoal)

China claims sovereign control over Scarborough Reef, 'indisputably' established by historic rights. China's historic claims significantly predate the current international law structures that govern questions of maritime boundary delimitation. The 1992 Law on the Territorial Sea and Contiguous Zone reaffirmed China's claim to sovereignty over the Zhongsha Islands, including Huangyan Island (Scarborough Reef). However, China has not historically exercised 'effective occupation and control' over the reef.

The Philippines claim that the Scarborough Shoal lies within its Exclusive Economic Zone (EEZ) as calculated under UNLOS. On 22 January 2013 the Philippine Government turned to the Permanent Court of Arbtration (PCA) in The Hague, seeking to declare Chinese territorial claims in its EEZ invalid. Philippines filed its claim against Beijing’s recent land grabbing and subsequent land reclamation activities in Scarborough Shoal and the Spratly Islands (claimed by both China and the Philippines) in the South China Sea.

Beijing refuses to recognise the authority of the Permanent Court of Arbitration (PCA) in The Hague. China has stated: “It will neither accept nor participate in the arbitration unilaterally initiated by the Philippines.” In October, however, the PCA ruled that: “Both the Philippines and China are parties to the convention [UNCLOS] and bound by its provisions on the settlement of disputes.” It also found that China’s refusal to participate did not deprive the court of jurisdiction and that the Philippines’ decision to commence arbitration unilaterally was not an abuse of the convention’s dispute settlement procedures. PCA Award on Jurisdiction and Admissibility (29 October 2015)

Although the Convention does contain provisions concerning the delimitation of maritime boundaries, China made a declaration in 2006 to exclude maritime boundary delimitation from its acceptance of compulsory dispute settlement, something the Convention expressly permits for maritime boundaries and certain other matters. On 7 December 2014, China’s Foreign Ministry published a “Position Paper of the Government of the People’s Republic of China on the Matter of Jurisdiction in the South China Sea Arbitration Initiated by the Republic of the Philippines” (“China’s Position Paper”). In its Position Paper, China argued that the Tribunal lacks jurisdiction because (a) “[t]he essence of the subject-matter of the arbitration is the territorial sovereignty over the relevant maritime features in the South China Sea”; (b) “China and the Philippines have agreed, through bilateral instruments and the Declaration on the Conduct of Parties in the South China Sea, to settle their relevant disputes through negotiations”; and (c) the disputes submitted by the Philippines “would constitute an integral part of maritime delimitation between the two countries.”

In the South China Sea Arbitration Award (12 July 2016) China’s claim to historic rights to resources was found incompatible with the detailed allocation of rights and maritime zones in the Convention. The Tribunal considered that prior to the Convention, the waters of the South China Sea beyond the territorial sea were legally part of the high seas, in which vessels from any State could freely navigate and fish. Accordingly, the Tribunal concluded that, as between the Philippines and China, there was no legal basis for China to claim historic rights to resources, in excess of the rights provided for by the Convention, within the sea areas falling within the ‘nine-dash line’. The tribunal concluded that China failed to exhibit due regard for the Philippines’ sovereign rights with respect to fisheries in its exclusive economic zone. Accordingly, China has breached its obligations under Article 58(3) of UNCLOS.

The Philippines submits that Scarborough Shoal and all of the high-tide features in the Spratly Islands are properly characterised as “rocks” under Article 121(3) of the Convention (paragraph 408.). While China has stated that it is entitled to an exclusive economic zone and continental shelf from the Spratly Islands, under the relevant provisions of the Convention and the above-referenced legislation, it has made no such claim specifically with respect to Scarborough Shoal (paragraph 461.). In the Tribunal’s view, Scarborough Shoal is a “rock” for purposes of Article 121(3) UNCLOS. The Tribunal finds that Scarborough Shoal includes five to seven rocks that are exposed at high tide and is accordingly a high-tide feature. (...) There is no evidence that the fishermen working on the reef make use of, or have any connection to, the high-tide rocks at Scarborough Shoal. Nor is there any evidence of economic activity beyond fishing (paragraphs 554. to 556.). The Tribunal concluded that under Article 121(3) of the Convention, the high-tide features at Scarborough Shoal are rocks that cannot sustain human habitation or economic life of their own and accordingly shall have no exclusive economic zone or continental shelf (paragraph 643.).

See a Global Arbitration Review (GAR) article South China Sea tribunal favours Philippines by Douglas Thomson and Allison Ross (July 12, 2016)

See a very informative blog by Julia Gaunce (September 8, 2016) The South China Sea Award and the duty of “due regard” under the United Nations Law of the Sea Convention

Paracel Islands

China (Hsi-sha Ch’ün-tao) - Taiwan (Xisha Qundao) - Vietnam (Quan Dao Hoang Sa)

The Paracel Islands lie about 250 miles (400 km) east of central Vietnam and about 220 miles (350 km) southeast of Hainan Island, China. Apart from a few isolated, outlying islands (Triton in the south, Lincoln in the east), they are divided into the Amphitrite group in the northeast and the Crescent group in the west.

Woody Island, occupied by China since 1956, is undergoing a major expansion of its runway and airport facilities: a 2,400-meter airstrip has been completely replaced with a new concrete runway measuring 2,920 meters in length, accompanied by a new taxiway, expanded runway aprons and adjacent large buildings under construction. Additional land reclamation is also underway on Woody Island, called Yongxing Dao in Chinese and Đảo Phú Lâm in Vietnamese.

Eighty kilometers southwest of Woody, on Duncan Island (seized by China from Vietnam in 1974) satellite images show landfill that has increased the size of the island by approximately 50 percent since April 2014. Known as Chenhang Dao in Chinese and Đảo Quang Hòa in Vietnamese, the island houses a military garrison, four radar domes, a concrete manufacturing plant, and a port that has recently been expanded via dredging and coral cutting. New buildings have also appeared on nearby Drummond Island, occupied by China.

Natuna Islands

China - Indonesia

On Nov. 12, 2015 China shocked the countries in the region by issuing a first-ever public statement on the Natuna Islands. According to Hong Lei, China’s Foreign Ministry spokesman, “The Indonesian side has no territorial claim to China’s [Spratly Islands]. The Chinese side has no objection to Indonesia’s sovereignty over the Natuna Islands.” Although the Natuna Islands are outside of China’s self-designated “Nine-Dash-Line” that lays claim to virtually all of the South China Sea, Natuna’s 200-miles exclusive economic zone (EEZ) protrudes into the area defined by the Nine-Dash-Line.

The Indonesian government does not currently recognize China’s so-called “Nine-Dash Line” (which overlaps with that EEZ) and so does not consider itself a claimant in any South China Sea-related maritime dispute. However, as the de facto leader and arbitrator among Association of Southeast Asian Nations (ASEAN) and with various member states locked in disputed territorial claims with Beijing, and with Chinese naval vessels penetrating Indonesian territorial waters around the Natuna Islands, Jakarta is essentially being forced to act. In October 2015, Bloomberg said that Indonesia is considering using drones and submarines to strengthen its grip over the gas-rich waters around the Natuna Islands in response to China’s growing military presence in the South China Sea.