聯合國大陸礁層界限委員會（簡稱CLCS）係聯合國依據聯合國海洋法公約（簡稱UNCLOS）第七十六條所成立。在沿岸國之大陸礁層延伸超過二百海浬時，由CLCS對於沿岸國就其延伸大陸礁層之外部界限所提出之資料加以審視，並就延伸大陸礁層外部界限之劃定相關事宜作成建議。若沿岸國延伸大陸礁層外部界限之劃定，係依據CLCS之建議作成，則該「外部界限」即享有法律上之拘束力、並具備終局之效力。所有的沿岸國均努力儘量蒐集各種科學證據，據以對更大的延伸大陸礁層主張其權利。在沿岸國向CLCS提交延伸大陸礁層外部界限之細節時，CLCS之審視與建議即對提案國之利益具有極大的重要性。就第三國而言，CLCS的建議也具有高度敏感性。因此，聯合國秘書長收受到任何提案後，此等第三國均有權以通知秘書長之形式對提案發表評論。實際上，曾有許多國家以此種方式發表其意見。第三國之所以提交此等通知，乃係在設法防制提案國不合理地擴大其延伸大陸礁層，意圖說服CLCS不贊同其提案，從而避免損害第三國對其延伸大陸礁層之主權權利。本文之重點，在於評估第三國如何在CLCS依據UNCLOS第七十六(8)條作成建議的程序中，以提出通知之方式確保其利益，並進而確保其在海洋劃界條約談判或司法爭端解決程序下之權利。本文第二部分將先處理CLCS相關規定，據以說明CLCS在建議程序中應扮演之角色。本文第三部分將檢視目前已公布的通知，進而探究第三國是如何回應依據UNCLOS附件Ⅱ第四條所提出之提案。本文將深入觀察第三國係如何建構其通知、以及其通知之內容與依據為何。此等相關實踐之觀察與分析，或可作為潛在第三國（包含我國）在考慮是否提出通知時之參考。 The CLCS was established by the U.N. in accordance with Article 76 of the UNCLOS. CLCS has a mandate to consider the data submitted by coastal states concerning the outer limits of their continental shelf in areas where those limits extend beyond 200 nautical miles (the extended shelf) and to make recommendations on matters related to the establishment of the limits of the extended shelf. The limits of the extended shelf established by a coastal state on the basis of such recommendations shall be final and binding. All coastal states are trying to collect as much scientific evidence as possible to serve as the bases for their entitlement of bigger extended shelf. The deliberations and recommendations of CLCS are vital to the interests of the coastal state which submits to CLCS particulars of the outer limits of its extended shelf (the Submitting State). Meanwhile, for third parties that have not submitted their own particulars to a given CLCS determination process while having actual or potential disputes, unresolved borders, or unresolved land or maritime disputes with the Submitting State, the recommendations of the CLCS can be very sensitive. Such third parties are given opportunities by the Secretary-General of the U.N. to express their comments, in the form of notifications, to any submission received by the Secretary-General. Many states have availed themselves of such opportunities to be heard. The concern underlying many of the notifications is that the CLCS may vindicate the extended shelves unjustifiably enlarged by the Submitting State, to the detriment of the sovereign rights of the third parties over their own extended continental shelf. The focus of this paper is on the potential third parties (including Taiwan) which may wish to take actions to preserve their interests and rights in parallel maritime delimitation treaty negotiations or judicial settlement processes through sending notifications in CLCS recommendation-making process under Article 76(8) of the UNCLOS. Relevant rules of CLCS which qualify the role to be played by CLCS in such processes will be addressed in the second part of this paper. It is believed that the passive role of CLCS needs to be fully understood before third parties start to formulate their notifications. In the third part of this paper, the author will examine the practices of third parties in responding to submissions under Article 4 of Annex II to the UNCLOS, by looking at those notifications already published. How these third parties have constructed their notifications and what they have put in those notifications will be observed closely. It is hoped that through such an exercise certain lessons can be learned by potential ‘third parties’ (including Taiwan) when they consider making notifications.