Navigating the South China Sea Public  

Article by Bobb Drake.

The contentious nine-dash line map, which is unrecognized outside the People’s Republic of China (PRC), has been in the news recently with its appearance on an ESPN broadcast and in DreamWorks animated feature film Abominable.

The nine-dash line represents the PRC’s (and Taiwan’s) claims in the South China Sea. These claims have been around since at least 1947 when the map was first used, but with the PRC’s increased land reclamation, energy exploration activities and naval patrols in the South China Sea in recent years, the conflict status has been ranked as worsening and as having a critical impact on US interests by the Council on Foreign Relations’ Global Conflict Tracker.

Nine-dash line (red) and overlapping national territorial claims in the South China Sea.

What’s at stake?

  • The South China Sea is a major strategic shipping lane for the PRC, the surrounding region and globally.
  • Eighty percent of China’s energy imports and nearly 40 percent of China’s trade pass through its waters, as do 50 percent of oil shipments and one-third of global trade.
  • The area is rich in fish and there are believed to be large oil and gas reserves beneath the seabed, although the territorial disputes have hindered exploration.
  • Without challenging China, the US risks undermining its security guarantees to its allies in the region and its future role as a maritime power in the area.

What are the competing claims in the region?

The area within the nine-dash line involves several distinct disputes involving a combination of occupations and claims by PRC, Taiwan, Vietnam, Philippines, Indonesia, Malaysia and Brunei. All disputed territories are claimed by both PRC and Taiwan, given the disputed sovereignty status between the two parties—which is a story for another day.

There are two main types of disputes:

  1. Land disputes – archipelagos, coral islands, coral reefs, atolls, sunken atolls; and
  2. Maritime boundary disputes – reach of continental shelf and extent of exclusive economic zones.

The disputes in the South China Sea overlapping in whole and in part with the nine-dash line are outlined below.

Land disputes

Disputed land: Administered by: Claimed by: Good to know:

Paracel Islands, Xisha, Hoàng Sa


PRC, Taiwan and Vietnam

Archipelago of 130 small coral islands and reefs.

The Paracel Islands were under French and Vietnamese control from the 1930s until PRC expelled South Vietnam from the islands in January 1974. As of February 2017, PRC has established 20 outposts on the islands, including three which have small harbors capable of berthing commercial and naval ships.

Pratas Islands, Dongsha Islands, Tungsha Islands


Taiwan, PRC

Three atolls in north South China Sea.

Macclesfield Bank

PRC (as part of Zhongsha Islands, which are claimed by PRC and Taiwan)

PRC, Taiwan, Philippines (eastern parts)

Elongated sunken atoll of underwater reefs and shoals.

Scarborough Shoal, Huangyan Dao, Bajo de Masinloc, Democracy Reef


PRC, Taiwan and Philippines

Shoal between Macclesfield Bank and Luzon Island, Philippines, formerly administered by Philippines.

Since the 2012 Scarborough Shoal standoff, PRC has taken over administration. The US did not militarily defend the Philippines in the standoff, resorting instead to “verbal protests” against China, which strained US-Philippines relations and solidified PRC’s expansionist goals in the area.

In 2016, an UNCLOS court upheld the Philippines’ claim on this area, rejecting PRC’s claim over the island and the nine-dash line in the South China Sea. The PRC does not recognize UNCLOS’ decision.

Spratly Islands, Nansha, Trường Sa, Kalayaan



PRC, Taiwan, Malaysia, Philippines, Vietnam and Brunei

Given their geographic location at the heart of the South China Sea, it is not surprising that the dispute over the Spratly Islands is the most complex and involves the most claimants, each holding various claims over land, maritime features, extension of continental shelf or exclusive economic zones.

To complicate the matter further, most of the maritime features have over a handful of different names, originating from the various countries involved in the disputes as well as from English, French, Portuguese and other colonial languages.

Disputed archipelagos and atolls in the South China Sea. Source: Hobe/Holger Behr 

Maritime boundary disputes

The nine-dash line overlaps with claims concerning the maritime boundaries and exclusive economic zones of Brunei, Indonesia, Malaysia, Philippines, Taiwan and Vietnam.

Maritime boundary: Disputed by: Good to know:

Along Vietnam’s coast

PRC, Taiwan and Vietnam

Since the summer of 2019, PRC has been conducting an energy exploration mission in waters controlled by Vietnam.

North of Borneo

PRC, Malaysia, Brunei, Philippines and Taiwan


North of Natuna Islands

PRC, Indonesia and Taiwan

The Natuna Islands are the northernmost non-disputed island group of Indonesia. Indonesia’s exclusive economic zone overlaps slightly with the nine-dash line.

Off Palawan and Luzon

PRC, Philippines and Taiwan


Islands in Luzon Strait PRC, Philippines and Taiwan  

Setting the course

Awareness of both the underlying issues and the parties involved is key to navigating such a maelstrom of disputes across so many countries without running aground. Armed with knowledge you are able to make informed decisions about whether and how to remain neutral when you represent all or parts of the South China Sea.

 On a map, you might label an area as ‘disputed’ and include the various names used by the claimants. In textual references, you might indicate the area is part of a contentious territorial or sovereignty dispute or perhaps omit any reference to territorial ownership whatsoever.

Inevitably, not everyone will be pleased all the time, but by understanding the risks, the consequences and knowing why you made the decision you made, you can batten down and remain even-keeled when dealing with potential criticism and backlash.

Bobb Nimdzi Insights


This article was researched and written by Bobb Drake. If you wish to find out more about this topic, please reach out to Bobb at

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