QI Huaigao, “An Analysis on Maritime Jurisdiction Claims and Maritime Delimitation Negotiation between China and Republic of Korea in the South Yellow Sea,” Asia-Pacific Security and Maritime Affairs, No. 5, 2022, pp. 46-63 (in Chinese). Summary There are some similarities between China and the Republic of Korea (ROK) on maritime jurisdiction claims. The breadth of the territorial sea, the contiguous zone, the exclusive economic zone, and the continental shelf, claimed by the two states, are the same. However, the two states have different legislation provided for baselines. China and the ROK have signed and ratified the UNCLOS, which demonstrates that the two states share some consensus on delimitation of maritime boundaries. Nevertheless, the two states still disagree on the principles of maritime delimitation to be applied in the South Yellow Sea (SYS). The Chinese side advocates delimitation in the principle of fairness and comprehensive consideration of all the circumstances and elements relating to delimitation, whereas the ROK side advocates delimitation in the median line. China and the ROK have officially started intergovernmental negotiations for maritime delimitation since 2015. By November 2021, the two states have held two vice minister-level official meetings and nine director-general-level meetings on the delimitation of the maritime boundaries. The two states have likely reached a preliminary agreement on the limits of the first-stage maritime delimitation area that does not involve a third party. China and the ROK are still facing four challenges in delimiting maritime boundaries in the SYS: first, the two states are divided about what circumstances should be relevant circumstances by using a three-stage approach; second, the two states challenge the effect of each other’s outmost islands and islets; third, the two states are in dispute over fisheries resources in the SYS; and fourth, the two states disagree with the jurisdiction of the Suyan Rock/Ieodo. The equidistance/relevant circumstances method can be applied to the maritime delimitation in the SYS under the precondition of achieving an equitable result. This article will apply the three-stage approach to delimitate the EEZ/continental shelf boundary between the two states. In the first stage of the three-stage approach, the two states will first construct a provisional equidistance line in the SYS. The provisional equidistance line will extend generally along the direction of south-southwest-southeast. In the second stage of the three-stage approach, the two states will determine whether there are any relevant circumstances that require an adjustment of the provisional equidistance line. There are two main relevant circumstances as follows: one is the effect of the outmost islands and islets on maritime delimitation, especially the effect of the ROK’s Soheugsan Island and Mara Island; the other is fisheries resources allocation. The fish resources in the Yellow Sea are highly migratory, and the catch and number of fishers on the Chinese side of the SYS are far greater than those in the ROK. In view of the above-mentioned two main relevant circumstances, China will probably argue that the provisional equidistance line should move towards the ROK. The two states could study the weighted line in 2012 Nicaragua v. Colombia. Technically, the two states can consider constructing a weighted line in the southern part of the relevant area by using a 1.5:1 ratio between China’s controlling points (Sheshan Island and Haijiao) and the ROK’s controlling points (Soheugsan Island and Mara Island). So the southern part of the provisional delimitation line will move towards the ROK. In the third stage of the three-stage approach, the two states will apply the disproportionality check. Under the adjusted equidistance line scenario, the ratio of the allocated relevant areas is approximately 1:1.17 in favor of China, and the ratio of the allocated the provisional measure zone (PMZ) of the 2000 China-ROK Fishery Agreement is approximately 1:1.44 in favor of China, according to the study of this article. Because the length of China’s relevant coast is longer than that of the ROK’s relevant coast in the SYS, it is reasonable to move the provisional equidistance line towards the ROK. To smoothly complete the maritime delimitation negotiation, the two states will have to comprehensively consider legal, political, and economic elements in the negotiation process. If China and the ROK can achieve an equitable solution on maritime delimitation, the two states will further advance the friendly relations in the future. Key words: China-ROK relations; maritime jurisdiction; maritime delimitation; consultation on the law of the sea; three-stage approach About the author: QI Huaigao is Professor and Vice Dean of Institute of International Studies, Fudan University. For more details about this article, please refer to the Chinese website.