Ieodo / Suyan Rock / Socotra Rock - 32°07.4' N. 125°10.9' E.

Socotra Rock is the subject of a territorial dispute between the Republic of Korea, which considers it to lie within its EEZ, referring to it as Ieodo or Parangdo, and the People's Republic of China which refers to it as Suyan Rock. Ieodo (Ieo Island) or Parangdo, called Suyan Rock [Suyan Jiao] by the Chinese, and Socotra Rock by Western sources, is a submerged reef 4.6 meters below sea level, located 149 kilometers southwest of Korea’s Marado Island, 394 kilometers east of China’s Haizhao Island, and 440 kilometers from the nearest Japanese island, Torishima. This reef is submerged at all times, during high and low tide. Under Article 121 of the Law of the Sea Convention, it is not entitled to generate any maritime zones - territorial sea, exclusive economic zone, or continental shelf - because it is not above water at high tide.

Socotra rock, in Lat. 32° 7' 22" N. Long. 125° 11' 16" E., is a coral patch over volcanic rock, which extends about 1/4 mile northeast and southwest and is about 60 yards wide, with a depth of probably less than 18 feet over it. The rock is very steep on its southern and eastern sides. There are depths of 27 to 30 fathoms, sand and mud, at a distance of about 1/4 mile all round the patch, excepting southwestward, where a rocky ledge with a least depth of 17 fathoms extends 1/2 mile, so the lead gives no warning until within the limit where the bottom becomes volcanic rock, scoriie, and broken coral.

The tidal stream sets strongly over the patch, on which there are overfalls and tide rips; the sea sometimes breaks on the rock. Very heavy overfalls and tide-rips are seen on the patch, and they extended about 1/2 mile N.E. and 1 mile S.W. "The shoalest spots are apparently at the extremes of the patch; at the N.E. extreme the sea was breaking occasionally, and it would probably break all over the patch with a moderate sea running. The overfalls and tide-rips should be visible from a ship for at least a mile, and, with a favorable light, the light-green color of the water over the coral patch should be seen from the same distance.

Apparently located between Jeju Island and I-eo Island, Parang-do (Parang Island) comprises a zone of indeterminacy between the real and the imaginary. Rick Spilman recounts that "The fisherman of Jeju have a legend of an island where the spirits of fishermen who perished at sea went to dwell. The mythical island was called both “Parangdo” and “Ieodo.” With the discovery of Socotra Rock, the South Korean government claimed a direct connection between these legends and the rock, claiming that the traditional saying that “One who sees Parangdo would never return” refers to the danger facing sailors when high waves allow the rock to break the surface."

Chinese sources relate that as early as the 4th century BC, the Chinese Shan Hai Jing (The Classic of Mountains and Seas), a compilation of legends, mentions Suyan Rock. From 1889 to 1890 the shoal was mapped as Suyan Rock by the Beiyang Fleet [Northern Seas Fleet] of China, one of the four modernised Chinese navies in the late Qing Dynasty. In the history of modern China, the Beiyang Fleet was always shadowed with a combination of heroism and humiliation. Literature works sing the praises of the patriotic behavior of the Beiyang naval officers, but on the other hand, depict the Qing Government’s corruption and weakness which humiliated China in the 1894 Sino-Japanese War.

But it was unknown to western navigators until the 19th Century. This patch is probably identical with 'Costa Rica' Breakers, reported 1868; 'Socotra' Rock, June 1900; 'Chiyucn' Shoal, September 1900; 'Bombay' Discoloured Water, October 1900. Telegraphic information, dated 1st August, 1901, was received from Lieutenant and Commander W. 0. Lyne, His Majesty's surveying-vessel "Waterwitch," that he had searched for the shoal reported north-eastward of the Great Yangtse bank by the Peninsular and Oriental Company's steamship "Socotra" in 1900, and found a rock, with a depth of 18 feet over it, in lat. 32° 7' N., long. 125° 11' E., or about 5 miles south-east- ward of the Socotra's position. It was placed on the Charts as Socotra Rock.

In 1951, South Korea installed a plaque on the Suyan Rock. In 1987 South Korea built a shipping warning beacon over the submerged rock. From 1995 to 2003, South Korea constructed the Ieodo Ocean Research Station over it, complete with helipad. In 2001 Socotra was renamed Ieodo by South Korea. China also claimed the rock was within its EEZ, though it is around 200 nautical miles from the mainland. Seoul rejected Beijing's claim, noting that Ieodo is less than 100 miles south of Marado, a treeless island of less than 1 square mile which is home to around 90 people. Marado is about 5 miles off the south coast of South Korea's Jeju island, a favorite South Korean holiday destination.

In 2006, China protested what it called “Korea’s unilateral actions in the area,” referring to the construction of the Ieodo Research Station. Both Korea and China have acknowledged that the station’s presence has no effect on the delimitation of the maritime boundary in this region. Korea and China agreed in December 2006 that there will be no territorial dispute over Ieodo, since it is a rock in the waters. Ieodo is much closer to Korea than to China, located 81 nautical miles south of Marado, compared to 147 nautical miles from Chenchienshan, a small island off the eastern coast of China. So the Korean government has consistently claimed that this area was clearly within the waters of the Korean EEZ even before the Meeting on the Delimitation of Maritime Boundaries between Korea and China.

In 2011 and 2012 the bilateral dispute over usage rights in overlapping waters surrounding Ieodo was reignited by clashes between Chinese fishermen and the South Korean Coast Guard. In one case in 2011, a Chinese fisherman stabbed to death a South Korean Coast Guard official. The two governments prevented these incidents from escalating; however, they appear to have fostered significant ill feelings among many South Koreans toward China. South Korean President Lee Myung-bak stated in March 2012 that if an agreement is reached about the exclusive economic zone between China and South Korea, Suyan Rock should belong to South Korea. In September 2013, Lee Myung-bak announced that South Korea would strengthen its defense in the water around Suyan Rock.

The Air Defense Identification Zone announced by China in November 2013 also includes the airspace over Ieodo and this has caused controversy. However, the ROK government said that it will not have much impact. But some argued that the ROK needed to modify its ADIZ to include the airspace over Ieodo. The South Korean government on 08 December 2013 announced plans to expand its air defense identification zone (ADIZ), which overlaps those of China and Japan. The move, which was first intended to be a response to Beijing's declaration of its own ADIZ that incorporated areas claimed by Seoul and Tokyo, might only serve to further escalate tensions regarding airspace in a region already riddled with territorial disputes. The key issue with the expanded Korean ADIZ is that it includes Ieodo Island, known internationally as Socotra Rock and Suyan Rock in Chinese, where the ADIZs of China and Japan already overlap.

After China announced the East China Sea ADIZ on 23 November 2013, the South Korea navy sent warships to patrol the waters around Suyan Rock on 02 December 2013.

Jon M. Van Dyke, professor at the William S. Richardson School of Law of the University of Hawaii at Manoa, noted in 213 that "Korea’s position that the maritime boundary in the Yellow Sea should be the equidistant line between Korea and China is consistent with recent decisions by the International Court of Justice and arbitral tribunals. China’s position that the line should follow the natural prolongation of the sea floor, on the other hand, does not have the support of recent decisions and does not appear to apply in any significant geographic way to the Yellow Sea, because (unlike the East China Sea, where the sea floor slopes gradually from China and then drops off sharply at the Okinawa Trough near Japan's small islands) the Yellow Sea has a flat, shallow and relatively featureless sea floor throughout. The sediments do not shift dramatically from clay to sand, but instead make a gradual transition, and the Yellow Sea includes areas where the sediments mix. It seems likely, therefore, that the equidistance line will emerge as the appropriate maritime boundary between China and Korea and, therefore, that Ieodo will be recognized as a feature within the exclusive economic zone of the Republic of Korea."