The Sino-Philippine Arbitration on the South China Sea Disputes was over on July 12, 2016, with a Merits Award in Philippine favor. Beijing rejected this arbitration and abstained from submitting written and oral arguments. Taiwan actively engaged in the debate with the Philippines since July 7, 2015. Not deemed as representative of China, Taiwan was considered capable of clarifying the meaning of the U-Shaped Line it first published in 1947 when seated in Nanjing, representing China then. The biggest maritime feature in the Spratly Islands, i.e. Taiping Island (Itu Aba), has been occupied by troops from mainland China since 1946 and then from Taiwan since 1956. The legal status of Taiping Island was the key to success of Philippine Submissions. The factual information from Taiwan became vital. This paper examines Taiwan’s role in this arbitration and the degree to which it could actually speak for China at such legal proceedings.

The countries in East Asia continue to have problems in maritime boundary delimitation. The collision on September 7, 2010 between a Chinese fishing vessel (Minjinyu) and a Japanese patrol boat in the waters near Diaoyu/Senkaku Islands is interesting to observe as a step in dispute settlement process. The differences between the PRC and Japan on maritime boundary delimitation for the East China Sea and the legal status of Diaoyu/Senkaku Islands are demonstrated by this incident. To see things in their context, it is necessary to observe the practices of East Asian countries in handling their maritime boundary delimitations, especially those involving islands with disputed legal status. The rules of international law relating to the pacific settlement of dispute and maritime delimitation dispute resolution, which involve a preliminary sovereignty dispute over islands, are also relevant as a much broader background. The author will examine why certain maritime delimitation cases are particularly hard to handle. The lessons drawn from this paper is inspiring for Taiwan, a long-time marginalized player in East Asian regional affairs. The author will examine the difficulties and opportunities for Taiwan in maritime boundary delimitation and offer a suggestion on how to accomplish such task with neighboring countries.