The UNCLOS regulates complex balance of rights and duties among State parties. Its text was deliberately left vague as a result of compromise between the negotiating parties. To develop the legal norms, judges and arbitrators have referred to other rules of international law through systematic integration, rules of reference, and broad applicable law. However, judicial practice has expanded subject-matter jurisdiction beyond the UNCLOS, causing antinomy between Articles 288, on jurisdiction, and 293 of UNCLOS, on applicable law. Part XV of the UNCLOS has created an invisible community that would ideally lead the UNCLOS Tribunals to develop and follow a pragmatic approach as to the limits of their subject-matter jurisdiction in order to provide for judicial coherence. When interpreting the treaty, the establishment of genuine links between disputes and substantive rules under the UNCLOS is necessary, by which other rules of international law are firmly anchored to the interpreted texts under the UNCLOS.

I. Introduction
II. The Approaches of the UNCLOS Tribunalsin their Judicial Incorporation of Other Rulesof International Law
    A. Systematic Integration
    B. Rules of Reference
    C. Broad Applicable Law
III. A Coherent Approach to IncorporatingOther Rules of International Law
    A. Constrained or Liberal? The “Genuine Link Test” forIncorporating Other Rules of International Law
    B. The Execution of the “Genuine Link Test”:Lessons from the Oil Platforms case
    C. Applying the “Genuine Link Test”: the Examination ofthe Approaches of the UNCLOS Tribunals
IV. Conclusion

• Ke Song(University of Edinburgh School of Law)