A. The Content of Paragraph 5(a)

The CLCS sets up a special rule to deal with submissions involving unresolved disputes. Rule 46 of the RoP, which is entitled “Submissions in case of a dispute between States with opposite or adjacent coasts or in other cases of unresolved land or maritime disputes”, provides that these submissions shall be considered in accordance with Annex I of the RoP that has the same title.Footnote ¹⁰ Paragraph 5(a) is a procedural rule contained in this Annex I. The paragraph provides that:

The wording of the first sentence of the Paragraph indicates that the CLCS shall not in principle consider a submission if it involves an unresolved land or maritime dispute. An exception to this principle is contained in the second sentence, which provides that the consent of all the parties to the dispute is the condition for the consideration of such a submission.

The reference to “a land or maritime dispute” implies that Paragraph 5(a) may apply to a broad range of disputes. A “land” dispute may refer to a dispute concerning territorial sovereignty over a piece of land or a land boundary, while a “maritime” dispute may cover all disputes concerning the interpretation or application of one or more rules of the international law of the sea including but not limited to those of UNCLOS.Footnote ¹¹ In practice, Paragraph 5(a) has been invoked in relation to submissions that involve, inter alia, delimitation disputes, territorial disputes, and the interpretation and application of one or more provisions of the UNCLOS.Footnote ¹²

The dispute must, however, be “related to the submission”.Footnote ¹³ In order to determine whether a dispute exists in relation to a submission, the RoP requires the coastal state to inform the CLCS if this is the case.Footnote ¹⁴ To make the determination, the CLCS also relies on the responses of other states to the submission made by the coastal state. The practice of the CLCS relating to Paragraph 5(a) shows that the threshold to determine the existence of a dispute falling within the scope of Paragraph 5(a) is low; in the view of the CLCS, such a dispute exists when, in response to a submission made by the coastal state, one or more states informs the United Nations Secretary-General, in the form of a note verbale, of the existence of an unresolved dispute between it and the coastal state.Footnote ¹⁵ In other words, a dispute concerning the existence of a land or maritime dispute is sufficient to trigger Paragraph 5(a).

Is this way of determining the existence of a dispute in accordance with the definition of a dispute in general international law? A dispute is defined as “a disagreement on a point of law or fact, a conflict of legal views or of interests between two persons”.Footnote ¹⁶ On the one hand, information from the coastal state and other states will bring to the surface the fact that the states concerned have such a disagreement or are in conflict. In some cases, evidence of the existence of a dispute is obvious when the coastal state and other states are involved in an extensive exchange of notes verbales in the years following the making of the submission. For example, in 2009, Malaysia and Vietnam made a joint submission to the CLCS in relation to the southern part of the South China Sea. This triggered an exchange of ten notes verbales between China, Indonesia, Malaysia, the Philippines, and Vietnam from 2009 to 2011.Footnote ¹⁷ The content of these notes verbales clearly shows there were unresolved land and maritime disputes between these states in the area in question, including the land dispute over the Spratly Islands between Vietnam, China, and the Philippines; the land dispute over North Borneo between Malaysia and the Philippines; and the maritime dispute over the maritime claims of China based on the nine-dash line. More recently, in response to the submission made by Malaysia in 2019, twenty-eight notes verbales and other diplomatic correspondences have been exchanged by eleven states, including Australia, China, France, Germany, Indonesia, Japan, New Zealand, the Philippines, the United Kingdom, the United States, and Vietnam.Footnote ¹⁸ The exchange of these diplomatic correspondences undoubtedly highlights the existence of a number of disputes concerning the maritime claims of China in the South China Sea.

On the other hand, it must be pointed out that the threshold to determine the existence of a dispute falling within the scope of the paragraph is lower than that of international courts and tribunals. The paragraph is expected to apply in the case of potential disputes,Footnote ¹⁹ which implies that in some cases the existence of a dispute is not required.Footnote ²⁰ An example of the application of the paragraph to a potential dispute is the case of the submission made by Yemen in respect of southeast of Socotra Island. The CLCS deferred the consideration of the submission on the basis of the note verbale made by Somalia requiring the CLCS to do so.Footnote ²¹ However, Somalia was, at the time, not sure whether there was a delimitation dispute with Yemen over the area subject to the submission. Somalia acknowledged that available evidence was not sufficient to establish the extent of its OCS, and thus only claimed that “[t]here may […] be a potential overlap between the areas of the continental shelf beyond 200 nautical miles claimed by the two coastal States” (emphasis added).Footnote ²² In the case of international courts and tribunals, a dispute over which they have jurisdiction must be an actual dispute, not a potential or hypothetical one.Footnote ²³ The different meaning of the term “dispute”, as understood by the CLCS and the international courts and tribunals, may be due to the fact the CLCS is a technical body and not a court of law.

B. The Impacts of Paragraph 5(a)

In practice, as of June 2021, Paragraph 5(a) has been invoked in relation to sixty-one submissions among which – with the consent of other states that were parties to the dispute related to the submission – the CLCS decided to proceed with only thirty-five submissions.Footnote ²⁴ Due to the absence of consent, the CLCS decided to defer the consideration of twenty submissions.Footnote ²⁵ For the remaining six submissions, the CLCS decided to consider only the parts of the submissions that were not related to the dispute.Footnote ²⁶ In short, of 101 submissions made to the CLCS so far, nearly two-thirds of them were affected by Paragraph 5(a), while one-quarter will not be considered, either wholly or in part, by the CLCS. For the coastal states that have had the consideration of their submissions deferred by the CLCS, they will be unable to establish the final and binding outer limits of their OCS. The absence of such outer limits potentially creates legal uncertainty as to the exercise of the rights and obligations of the coastal states and those of other states. Furthermore, as noted at the beginning of this paper, if the coasts of the coastal state face open seas, such an absence means that the limits of the Area are undetermined, which may affect the exploration and exploitation of the resources of that area by the ISA due to the lack of legal certainty.

Furthermore, due to the persistent nature of the disputes between the states concerned, the consideration of some submissions has been deferred for a long time; for others the deferral may be indefinite. One example is the three submissions made in respect of the South China Sea by Malaysia and Vietnam. The exchange of notes verbales between the states concerned, as mentioned above, shows that there is no hint that Malaysia and Vietnam might obtain the consent from the other parties to the dispute, especially China. Consequently, it is highly unlikely that the CLCS will consider these submissions in the foreseeable future. The other example involves the submissions made by the United Kingdom and Argentina concerning the outer limits of the OCS of the Falklands/Malvinas, over which sovereignty is claimed by both states.Footnote ²⁷ In 1982, both states were involved in a war over the control of the islands – the so-called “Falklands War” in English or “Guerra de las Malvinas” in Spanish. It is unlikely that either state will give consent for the consideration of the submission of the other state.

A. Paragraph 5(a) and UNCLOS: A Preliminary Observation

At first glance, Paragraph 5(a) seems to lack a legal basis under UNCLOS. Firstly, Paragraph 5(a) introduces new factors that are not expressly provided for or mentioned in UNCLOS.Footnote ²⁸ It gives the CLCS the “right” not to consider a submission and not to make recommendations. According to Article 76(8), the Commission “shall make recommendations to the coastal State”. The word “shall” indicates a legal obligation to make recommendations. In the absence of a permissive rule in UNCLOS, Jensen observes that by giving the CLCS such a “right”, Paragraph 5(a) enables the CLCS to act contrary to this duty to make recommendations per Article 76(8).Footnote ²⁹ At the same time, the paragraph gives other states the “right” to block the consideration of a submission made by a coastal state. Nothing in UNCLOS offers an obvious legal basis for such a right. The creation of such rights for the CLCS and other states arguably puts the coastal state at a disadvantage. One may argue that in order to have its submission considered by the CLCS, the coastal state is subject to the condition of obtaining consent from other states – a condition that is not provided for by UNCLOS. If the coastal state fails to obtain the consent required under Paragraph 5(a), it is denied the right to have the outer limits of its OCS established in accordance with Article 76. Secondly, the delay in the establishment of the outer limits of the OCS is contrary to one of the objects and purposes of UNCLOS, which is to “create certainty about the extent of the continental shelf, and hence the limits of the Area”.Footnote ³⁰

As the impact of Paragraph 5(a) is significant, one question that arises is whether Paragraph 5(a) is in accord with UNCLOS. The answer to this question depends on the considerations of the five issues discussed below.

B. Did the CLCS Have the Power to Adopt Paragraph 5(a) in the First Place?

First of all, as Paragraph 5(a) is a procedural rule adopted by the CLCS, the immediate issue that needs to be addressed is whether the CLCS has the power to adopt such a rule in the first place. UNCLOS does not contain any provision expressly governing this issue. While the CLCS is not an international organization, the doctrine of implied powers in international institutional law is often cited to argue that the CLCS possesses such powers.Footnote ³¹ According to this doctrine, an international organization may possess “implied powers”; namely, powers that are not explicitly conferred upon it by the constitutive instrument but are necessary for it to effectively exercise its functions and realize its objectives.Footnote ³² The key function of the CLCS is to consider the submissions made by coastal states and to make recommendations to those states.Footnote ³³ In order to discharge this function, there must be some procedural arrangements on how the CLCS operates, such as rules on sessions and meetings, the venue, agenda setting, the election of a chairperson and the scope of his or her powers, the working language, the voting procedure, the quorum, and the step-by-step procedure for the consideration of submissions. It is beyond doubt that without these arrangements the CLCS will be unable to operate; thus they are essential for the CLCS to discharge its functions. However, the Convention does not contain any provision that provides the CLCS with any such arrangement; therefore, in order to discharge its functions, the CLCS must have an implied power to adopt its own procedural rules.

Furthermore, states parties to UNCLOS did not object to the CLCS having such an implied power. Indeed, the rules of procedure of the CLCS were first drafted at the request of the Meeting of States Parties.Footnote ³⁴ Some rules, including Paragraph 5(a), were submitted to the Meeting of States Parties for their feedback prior to the CLCS adopting them.Footnote ³⁵ The absence of any objection to the drafting and adoption of the RoP by the CLCS implies the acquiescence of states parties to the power of the CLCS to make its own rules of procedure.

Stating that the CLCS possesses the power to adopt the rules of procedure does not necessarily mean that this power is without limitation. On the contrary, those rules must be in accordance with UNCLOS.Footnote ³⁶ In the other words, the RoP of the CLCS must in any case not be contrary to UNCLOS – the treaty that established the CLCS. Therefore, the next issue to be examined is whether Paragraph 5(a) is contrary to any provision of UNCLOS.

C. Paragraph 5(a) and Article 9 of Annex II to UNCLOS

Article 9 is first examined because Paragraph 5(a) is often suggested as having implemented this article.Footnote ³⁷ This article provides that “[t]he actions of the Commission shall not prejudice matters relating to delimitation of boundaries between States with opposite or adjacent coasts”.

The term “prejudice” means “cause harm to (a state of affairs)”.Footnote ³⁸ According to Serdy, there are two ways to read this article: “either that the CLCS must take care to avoid actions that prejudice delimitations, or […] that, provided the CLCS does not stray beyond its technical task, by definition nothing it does is capable of bringing about such prejudice”.Footnote ³⁹ He favours the latter reading.Footnote ⁴⁰

By contrast, Oude Elferink argues that the article does not provide that the actions of the CLCS “are without prejudice” to the matters related to delimitation, but it “instead instructs the Commission to ensure that no such prejudice results from its actions”.Footnote ⁴¹ This interpretation is more in line with the ordinary meaning of the phrase “shall not prejudice”. The word “shall” indicates an obligation while the word “prejudice”, which is a verb, indicates an active obligation not to make detrimental impacts.Footnote ⁴² The second interpretation implies that there is no potential for the actions of the CLCS to prejudice the matters concerning delimitation. This presumption is not always right, as discussed in the following paragraphs of this section, and, more importantly, overlooks the guarantee offered by Article 76(10) of UNCLOS, as discussed in Section D.

The relationship between Paragraph 5(a) and Article 9 is also touched upon by the International Court of Justice (ICJ) in its recent judgments. In its 2016 judgment in Nicaragua v. Colombia, the Court observed that although UNCLOS distinguishes between the delineation and delimitation of the OCS, “the two operations may impact upon one another” and that “[t]he CLCS has, in its internal rules (Article 46 and Annex 1), established procedures, in accordance with Article 9 of Annex II to UNCLOS, to ensure that its actions do not prejudice matters relating to delimitation” (emphasis added).Footnote ⁴³ This obiter dictum seems to reflect the first reading of Article 9, which may be interpreted as confirmation from the Court on the accordance of Paragraph 5(a) with Article 9.

However, in its 2017 Somalia v. Kenya judgment, while citing the dictum, it did not refer to the phrase “in accordance with Article 9”. Instead, it stated that: “as the Court has highlighted, ‘it is possible that the two operations may impact upon one another’ and the rules of the CLCS therefore contain provisions that seek ‘to ensure that its actions do not prejudice matters relating to delimitation’”.Footnote ⁴⁴ It then observed that Paragraph 5(a) – together with other rules contained in Rule 46 and Annex I – is the approach taken by the CLCS, without mentioning whether it is in accordance with Article 9.Footnote ⁴⁵ The ICJ's view in this judgment is more moderate in the sense that it simply acknowledged the approach of the CLCS and refrained from touching on the question of the accordance of the approach with UNCLOS.

In some cases, the application of Paragraph 5(a) may indeed be detrimental to the question of delimitation by preventing the delimitation from being conducted.Footnote ⁴⁶ As a matter of principle, delimitation only arises if two or more coastal states have overlapping entitlements. In the words of the International Tribunal for the Law of the Sea (ITLO), “[d]elimitation presupposes an area of overlapping entitlements”, and thus “the first step in any delimitation is to determine whether there are entitlements and whether they overlap”.Footnote ⁴⁷ The establishment of the outer limits of the OCS is to clarify whether the coastal state has the entitlement, and whether that entitlement overlaps with those of other states.

However, when Paragraph 5(a) is applied it blocks the consideration of a submission and thus prevents the establishment of the outer limits of the OCS. As a result, uncertainty remains with regard to the existence and the scope of the entitlement of the coastal state to the OCS. The ITLOS acknowledges that blocking the consideration of the submission at the CLCS by applying Paragraph 5(a) may, in some cases, put a court or tribunal in a position that prevents it from delimitating the OCS.Footnote ⁴⁸ Those are cases in which a court or tribunal concludes that, in the absence of the outer limits of the OCS, “there was significant uncertainty as to the existence of a continental margin in the area in question”.Footnote ⁴⁹ In such cases, the application of Paragraph 5(a) would have a detrimental impact upon the delimitation. It creates a deadlock: on the one hand, the existence of a delimitation dispute prevents the CLCS from considering a submission; on the other hand, blocking the CLCS from considering a submission prevents a court or tribunal from settling that delimitation dispute. The consequence is, as noted by the ITLOS, to put all the parties to the dispute “in a position where they may be unable to benefit fully from their rights over the continental shelf”.Footnote ⁵⁰

D. Paragraph 5(a) and Article 76(10) of UNCLOS

As well as Article 9, some commentators have also suggested that Paragraph 5(a) implements Article 76(10) of the Convention.Footnote ⁵¹ In their view, Article 76(10) and Article 9 have similar rules. However, the two provisions have different meanings.Footnote ⁵² Article 76(10) provides that: “[t]he provisions of this article are without prejudice to the question of delimitation of the continental shelf between States with opposite or adjacent coasts”.

An ordinary reading of the provision indicates that it provides a legal guarantee against any prejudice to the question of delimitation of the continental shelf. This is different from Article 9, which specifically imposes upon the CLCS an active duty not to take any acts that prejudice matters related to delimitation.

The phrase “without prejudice” in Article 76(10) means “without detriment to any existing right or claim”.Footnote ⁵³ “Detriment” means “the state of being harmed or damaged” or “a cause of harm or damage”.Footnote ⁵⁴ Therefore, in accordance with the ordinary meaning of these terms, Article 76(10) provides a safeguard clause guaranteeing that the delineation of the continental shelf shall have no detrimental implication upon the question of delimitation that is pending between the coastal state and other states.

Furthermore, this provision implies that the matter of delineation of the continental shelf as stipulated under Article 76 is distinct from the matter of delimitation, which is exclusively governed by Article 83.Footnote ⁵⁵ The delineation process involving the CLCS is not intended to settle in any way delimitation disputes between states.Footnote ⁵⁶ The jurisprudence of international courts and tribunals confirm that delineation and delimitation are two separate processes.Footnote ⁵⁷ However, the ICJ has repeatedly concluded that, although they are distinct processes, the two may impact upon one another.Footnote ⁵⁸ Article 76(10) thus ensures that any impact created by the delineation process is not detrimental to the question of delimitation. It means the rights of other states that have overlapping entitlements with the coastal state shall not be negatively affected by the application of Article 76 to establish the final and binding outer limits of the OCS via the procedure involving the CLCS.Footnote ⁵⁹ Particularly, the finality and binding effect of the outer limits are not opposable to states that have an entitlement that overlaps with a coastal state.Footnote ⁶⁰ With the safeguard under Article 76(10), no prejudice may occur that justifies the need for Paragraph 5(a).Footnote ⁶¹ Consequently, some commentators have suggested that “other states should in principle not object to the consideration of a submission by a coastal state which raises issues of delimitation”, because “the consideration of a submission and subsequent recommendation will not prejudice their rights”.Footnote ⁶²

The above discussion shows that Paragraph 5(a) overlooks the legal guarantee provided by Article 76(10). The CLCS seems to justify the adoption of the paragraph on the presumption that the consideration of a submission involving an unresolved dispute and the making of recommendations causes harm to the matter related to delimitation, and that the CLCS is under the duty not to take any of such actions.Footnote ⁶³ This presumption is legally incorrect. By virtue of Article 76(10), no prejudice may occur from the acts of the CLCS to the question of delimitation of the continental shelf. One commentator has argued that saying “it is without prejudice” does not mean “it is indeed without prejudice”, and that the CLCS should take a more cautious approach, as is reflected in Paragraph 5(a).Footnote ⁶⁴ This argument is only correct if the CLCS, by making recommendations, draws a boundary line delimiting the overlapping continental shelf between states. This scenario is unlikely to happen as the CLCS is to make recommendations to coastal states individually. The CLCS is not going to make recommendations on the boundary line between a coastal state and other states. The above discussion indicates that the CLCS overlooks Article 76(10).

In short, since Article 76(10) provides a guarantee that prevents the delineation process from prejudicing the delimitation process between the coastal state and other states, Paragraph 5(a) is not necessary. However, such an unnecessary rule has had a prejudicial impact upon the normal implementation of the delineation process of the OCS involving the CLCS. It creates a deadlock to the process and thus prevents the coastal State from establishing the final and binding outer limits of its OCS. Paragraph 5(a) cannot be justified by Article 76(10).

E. Paragraph 5(a) and Article 76(8) and Article 3(1) of Annex II to UNCLOS

Under Article 76(8), the CLCS has the duty to make recommendations to the coastal state concerning the establishment of the outer limits of the OCS. This duty is enforced by Article 3(1)(a) of Annex II to UNCLOS, which provides that the function of the CLCS is, inter alia, to consider the submission made by the coastal state and to make relevant recommendations. While UNCLOS does not expressly provide for an exception to the duty, Busch argues that Paragraph 5(a) must be considered as such an exception.Footnote ⁶⁵ She explains her view as follows:Footnote ⁶⁶

On the one hand, the explanation overlooks the distinction between the exercise of the duty and functions of the CLCS as part of the delineation process of the OCS and the settlement of delimitation disputes relating to OCS between states. The duty and function of the CLCS are to recommend the coastal state on how to establish the outer limits of the OCS in accordance with Article 76. As discussed above, by virtue of Article 76(10), the delineation process involving the CLCS does not, at the same time, settle an unresolved delimitation dispute between the states concerned. The outer limits are not the delimitation line. In this regard, Serdy is correct in observing that, as long as the CLCS acts within its technical functions, no prejudice may occur to the question of delimitation.Footnote ⁶⁷

On the other hand, the right of the CLCS to defer the consideration of a submission involving a dispute under Paragraph 5(a) may directly derive from the duty and functions of the CLCS. If the settlement of a dispute is a prerequisite for the performance of the duty and exercise of the functions of the CLCS, the existence of such an unresolved dispute forms the basis for the CLCS not to make recommendations. That is the case involving a sovereignty dispute between the coastal state and other states over a piece of land that forms the OCS.Footnote ⁶⁸ In this case, it is unknown to the CLCS whether the submission was made by “the coastal state”, and which state is “the coastal state”. It does not have a duty to make recommendations to a state that is not a coastal state.

For example, and as mentioned above, there remains an unresolved sovereignty dispute between Argentina and the United Kingdom over the Falklands/Malvinas. Both states made submissions in respect of the islands’ OCS.Footnote ⁶⁹ In law, there can only be one state that has sovereignty over the islands, which is the only state that can be considered as the coastal state in respect to the OCS. That is the state that has the obligation to make a submission to the CLCS, which is the only submission that will be considered by the CLCS. This is the only state to which the CLCS has a duty to make recommendations. Pending the settlement of the dispute, and without the prior consent of both states, the CLCS may wrongly exercise its functions by considering the submission that is not made by the coastal state, and by making recommendations to a state that is not the coastal state. Logically, the CLCS must have the right to refuse to consider the submission. It is thus directly derived from its duty and functions.

Another type of dispute that requires the CLCS to refuse to consider a submission is a dispute concerning the legal status of an island that generates the OCS subject to the submission. Under UNCLOS, only one type of island has the potential to have an OCS – the so-called “fully-entitled islands” under Article 121(2). Under Article 121(3), a rock that is also an island does not have a continental shelf of its own. When a dispute arises over whether an island is an Article 121(2) island, it is unknown to the CLCS whether there is an OCS, the outer limits of which the CLCS has a duty to make recommendations. Consequently, if it proceeds with the consideration of the submission and then makes recommendations, it will perform its duty and exercise its functions on the hypothetical presumption of the existence of an OCS.

It may be argued that the CLCS should not consider a submission if it is unsure that the entitlement exists.Footnote ⁷⁰ Otherwise, it may face an awkward situation if the feature in question turns out later not to be an Article 121(2) island. In practice, the treatment of the CLCS of the submission made by Japan indicates that the CLCS chooses the middle way. Japan made a submission to the CLCS in 2008 in an attempt to extend the proposed outer limits of the continental shelf beyond 200 nautical miles from Okinotorishima – a small group of mid-ocean islands.Footnote ⁷¹ With this submission, Japan showed that it considered these islands as Article 121(2) islands. However, the view of Japan was opposed by both China and South Korea.Footnote ⁷² They believed that these islands should be considered as rocks that do not generate a continental shelf.Footnote ⁷³ They asked the CLCS not to consider the portion of the submission concerning Okinotorishima.Footnote ⁷⁴ The CLCS acknowledged that it was not competent to address the issues concerning the interpretation or application of Article 121.Footnote ⁷⁵ Therefore, it decided to consider the whole submission, but deferred the approval of the parts of the recommendations in respect of Okinotorishima.Footnote ⁷⁶

It is arguable that the decision to approve certain parts would likely be suspended until the status of the islands was clarified, or at least until China and South Korea withdraw their objections. The approach of the CLCS in this case seems to indicate that if a submission involves a dispute on the legal status of an island, the CLCS shall consider the submission on the hypothesis that it may have an entitlement to an OCS, while not approving the relevant parts of the recommendations. It is not yet clear what the reason was behind this approach.

Another reason for the CLCS not to consider the two kinds of disputes above is that the applicable law of these disputes is not within the interpretative competence of the CLCS. In order to make recommendations in accordance with Article 76, as required under Article 3(1) of Annex II to UNCLOS, it is beyond doubt that the CLCS must be deemed to have the competence to interpret Article 76 so far as it is necessary to discharge its functions.Footnote ⁷⁷ Some argue that, besides Article 76, the CLCS may also have the same competence with respect to other provisions of UNCLOS to the extent that it is necessary to carry its functionsFootnote ⁷⁸ such as those contained in Annex II to UNCLOS.Footnote ⁷⁹ If the subject matter of the dispute involves these provisions, the CLCS may interpret them to the extent that is necessary for it to consider the submission concerned and make recommendations. This should not be interpreted as settling the dispute in question, but rather as merely exercising the functions of the CLCS. If the subject matter of the dispute involves legal rules that are beyond the interpretative competence of the CLCS, the presence of the dispute remains a bar for the CLCS to perform its duty and exercise its functions because the settlement of the dispute is a prerequisite for the CLCS to do so. Examples of this type of dispute include disputes concerning territorial sovereignty or the legal status of an island. The CLCS has indeed acknowledged that it has no competence to interpret Article 121.Footnote ⁸⁰

In sum, directly deriving from the duty and functions of the CLCS, the CLCS must have the right not to consider a submission involving a dispute if it satisfies two conditions: (i) the settlement of the dispute is a prerequisite for the CLCS to perform its duty and to exercise its function, and that (ii) the CLCS has no interpretative competence in respect to the applicable law of these disputes. The above discussion may also justify the fact that Paragraph 5(a) applies to submissions involving land or maritime disputes other than delimitation disputes.Footnote ⁸¹

The discussions contained in the above Sections C to E show that Paragraph 5(a) is not fully in accordance with Article 76(10) and Article 9 of Annex II to UNCLOS. It may be in accordance with the duty and functions of the CLCS as stipulated in Article 76(8) and Article 3 of Annex II to UNCLOS in the case of submissions involving an unresolved dispute, the settlement of which is a prerequisite for the CLCS to perform its duty and exercise its functions. Examples of such disputes include circumstances where there is a sovereignty dispute over land territory that generates the OCS, or a dispute concerning the legal status of an island that generates the OCS. This conclusion does not mean that, except for these types of disputes, the application of Paragraph 5(a) in the case of other disputes is not in accordance with UNCLOS. As shown below, the attitude of states parties toward the paragraph offers a potential justification.

F. Paragraph 5(a) and the Attitude of States Parties: Interpretation by Subsequent Practice?

Oude Elferink has suggested that Paragraph 5(a) may be considered as an interpretation by subsequent practice under Article 31(3) of the 1969 Vienna Convention on the Law of Treaties.Footnote ⁸² The International Law Commission (ILC) has observed that subsequent practice may result in “narrowing, widening, or otherwise determining the range of possible interpretations”.Footnote ⁸³ To this effect, Paragraph 5(a) may be considered as the interpretation that widens the meaning of Article 9 of Annex I to UNCLOS and, possibly, also Article 76(10), despite the fact that the above discussion indicates that the paragraph is not fully in accordance with both provisions. The condition for the paragraph to be considered as an interpretation by the subsequent practice of states parties to UNCLOS is that the practice must establish that the paragraph reflects “the agreement of the parties regarding its interpretation”.Footnote ⁸⁴ In the case of Paragraph 5(a), such an agreement seems to be established by the absence of objections from states parties for more than twenty years from the date it was adopted. As noted above, the paragraph has been invoked to block, wholly or partly, the consideration of twenty-five submissions. No state has ever raised an objection to the paragraph itself. This includes the coastal states that made those submissions; they objected to the application of the paragraph to block the consideration of their submissions but did not object to the existence of the paragraph itself. In some cases, they actively confirmed their ongoing attempt to obtain consent from other parties to the dispute. For example, in the executive summary of the joint submission made by Malaysia and Vietnam, both states confirmed that there was an unresolved dispute over the area subject to the submission and that they have undertaken efforts, unsuccessfully, to secure the non-objection of the other relevant coastal states.Footnote ⁸⁵

However, by referring to the assurance under Paragraph 5(a) of Annex I to the RoP that the joint submission is without prejudice to the position of any party to a land or maritime dispute, they requested the CLCS to consider the joint submission.Footnote ⁸⁶ In the presentation of the joint submission before the CLCS, the representatives of Malaysia and Vietnam reportedly emphasized that “the submission was without prejudice to the question of delimitation between States and that paragraph 5(a) of annex I of the rules of procedure should not be invoked”.Footnote ⁸⁷ The statement indicates that both states did not object to Paragraph 5(a), but objected to its invocation by other states to block the consideration of the submission.

In another case, the coastal state clearly supported the invocation of Paragraph 5(a) by another state to block the consideration of its submission. For example, in the executive summary of the submission made by France in 2014, in respect of the area of Saint-Pierre-et-Miquelon, Canada invoked Paragraph 5(a) to block the consideration of the submission. France recognized that there was an unresolved maritime dispute between itself and Canada over the area subject to the submission. At the same time, “France endorses, with a view to its application”, Paragraph 5(a).Footnote ⁸⁸ The absence of an objection to Paragraph 5(a) indicates that there is likely an agreement between states parties to accept Paragraph 5(a) as the interpretation of Article 9 of Annex II to UNCLOS. This conclusion is further cemented when looking into the drafting history of Paragraph 5(a). No objection of states parties to the paragraph was recorded when the draft paragraph was submitted to the ninth Meeting of States Parties (SPLOS) for feedback.Footnote ⁸⁹ The report of the eighth SPLOS shows that no state objected to the draft Paragraph 5(a).Footnote ⁹⁰

In addition, Paragraph 5(a) may be also be considered as a tacit modification to UNCLOS by subsequent practice.Footnote ⁹¹ However, in international law, the question of whether subsequent practice may modify a treaty remains controversial. Some commentators argue that a treaty may be modified by subsequent practice.Footnote ⁹² Others disagree.Footnote ⁹³ It is beyond the scope of this article to examine which view better reflects contemporary international law. Therefore, the question of whether Paragraph 5(a) can be considered as a modification to UNCLOS does not have a definite answer.

A. Paragraph 5(a) Should Not Apply to Submissions Involving Delimitations Disputes

As shown in the discussion in Section D, Article 76(10) provides a legal guarantee to ensure that the delineation process involving the CLCS shall not prejudice the delimitation process. This guarantee is sufficient to protect the rights of other states that have an entitlement to the area subject to the submission made by a coastal state. Furthermore, the completion of the delineation process involving the CLCS brings certainty to the extent of the overlapping area and thus facilitates the delimitation process.Footnote ⁹⁴ With the existence of the guarantee under Article 76(10) and the benefits of completing the delineation process, it is submitted that Paragraph 5(a) is not necessary to cover submissions involving delimitation disputes. It should be thus modified to exclude this type of disputes.

The above proposal is supported by the practice of how other states responded toward submissions made by a coastal state that concerned a delimitation dispute only. The majority of states gave consent to the consideration of those submissions. When doing so, some made an explicit reference to Article 76(10); for example, India,Footnote ⁹⁵ New Zealand,Footnote ⁹⁶ Fiji,Footnote ⁹⁷ Tonga,Footnote ⁹⁸ France,Footnote ⁹⁹ Pakistan,Footnote ¹⁰⁰ Oman,Footnote ¹⁰¹ Indonesia,Footnote ¹⁰² Portugal,Footnote ¹⁰³ Mexico,Footnote ¹⁰⁴ and Morocco.Footnote ¹⁰⁵ Some did not explicitly refer to Article 76(10) but repeated the wording of the provision; for example, Timor-Leste,Footnote ¹⁰⁶ Iceland,Footnote ¹⁰⁷ Suriname,Footnote ¹⁰⁸ Barbados,Footnote ¹⁰⁹ Trinidad and Tobago,Footnote ¹¹⁰ and the United Kingdom.Footnote ¹¹¹ Tonga,Footnote ¹¹² France,Footnote ¹¹³ Pakistan,Footnote ¹¹⁴ Oman,Footnote ¹¹⁵ Indonesia,Footnote ¹¹⁶ Portugal,Footnote ¹¹⁷ Mexico,Footnote ¹¹⁸ and Morocco.Footnote ¹¹⁹ Some did not explicitly refer to Article 76(10) but repeated the wording of the provision; for example, Timor-Leste,Footnote ¹²⁰ Iceland,Footnote ¹²¹ Suriname,Footnote ¹²² Barbados,Footnote ¹²³ Trinidad and Tobago,Footnote ¹²⁴ and the United Kingdom.Footnote ¹²⁵ Some states concluded an agreement in which they reassured one another that consideration of the submission by the CLCS, and its subsequent recommendations, shall not prejudice the question of delimitation.Footnote ¹²⁶

If submissions involving delimitation disputes are excluded from the scope of application of Paragraph 5(a), the CLCS will be enabled to consider more submissions, especially those that only involve a delimitation dispute such as the submissions made by Yemen, Fiji, or Palau. These are submissions where the reactions from other states only raised the issue of maritime delimitation.

B. Submissions Involving Other Land or Maritime Disputes

The discussions in Section E indicate that Paragraph 5(a) should cover disputes, the settlement of which is a prerequisite for the CLCS to perform its duty and exercise its functions. They include a sovereignty dispute over land territory that generates the OCS subject to the submission, or the dispute concerning the legal status of an island that generates the OCS subject to the submission. There may be other disputes of similar nature such as a dispute concerning the validity of baselines.Footnote ¹²⁷ The CLCS should develop a test to identify such types of disputes. If other states wish to block the consideration of a submission due to the presence of an unresolved dispute, they should be required to provide an explanation as to how the settlement of the dispute concerned is a prerequisite for the CLCS to perform its duty and exercise its functions. The test may be added to Paragraph 5(a).

One may argue that as a technical body composed of scientists, not lawyers,Footnote ¹²⁸ the CLCS may face difficulties in evaluating the test. It is true that members of the CLCS are not required to have legal expertise, and in practice few members of the CLCS have such expertise.Footnote ¹²⁹ However, this should not be a bar for the CLCS to determine whether a dispute involving a submission is required to be settled before the CLCS can consider the submission.

The first reason is that the RoP allows the CLCS to seek external advice from specialists.Footnote ¹³⁰ The CLCS may request legal advice to assist it to make the determination. In this regard, it should be noted that the CLCS has in the past asked for legal advice from the Legal Counsel of the United Nations on the privileges and immunities of its members,Footnote ¹³¹ the procedure to deal with the breach of confidentiality rules,Footnote ¹³² and the possibility of submitting additional information by a coastal state during the consideration of its submission.Footnote ¹³³ While the question of whether legal counsel should assist the CLCS in determining the applicability of Paragraph 5(a) and the procedure to seek legal advice from other specialists may need to be further examined, at least, the RoP do offer a basis for the CLCS to seek external legal advice.

The second reason why the CLCS's lack of legal expertise does not prevent the proposed modification is that the CLCS is not a court of law,Footnote ¹³⁴ but a recommendatory body. Whatever it recommends does not have a legally-binding effect upon the states concerned. What the CLCS is required to do is to use its best efforts to evaluate the information that it has at hand concerning the dispute with or without assistance from external advice.

While the lack of legal expertise should not be a reason for not modifying Paragraph 5(a), the attitude of states parties is likely the most significant obstacle. As noted above, the paragraph has the general support of states parties. During more than twenty years of its application, no objection has been recorded. Even the coastal states that have had their submissions blocked by the paragraph have not objected to the paragraph itself. Any attempt to modify Paragraph 5(a) may face pushback from states parties, particularly those states that invoked Paragraph 5(a) to block the consideration of a submission. They may go against a modification if the outcome removes the effect of their invocation in the past.Footnote ¹³⁵

However, if states parties conclude that the proposed modification to the paragraph does not affect their rights and brings more benefits than the current Paragraph 5(a), they may support such modifications. It is quite clear that the proposed modifications will allow the CLCS to consider more submissions and thus contribute to removing legal uncertainty in more areas in the world's oceans and seas. Moreover, it also contributes to the realization of one of the objects and purposes of UNCLOS – that is to create legal certainty about the outer limits of the continental shelf and thus the limits of the area. Furthermore, the proposed modification of Paragraph 5(a) would not be intended to completely remove the right to block the consideration of a submission involving an unresolved dispute. The other states still retain such a right, but are subject to certain conditions.