LNELecture Notes in Education, Arts, Management and Social ScienceTBA2705-053XWHIOCE PUBLISHING PTE. LTD.10.18063/LNE.v4i2.1521ArticleThe Application Dilemma and Regulatory Path of Dissenting Opinions in International Investment Arbitrationhttps://artdesignp.com/journal/LNE/4/2/10.18063/LNE.v4i2.1521HanZhengzhong2026422026-02-26Sudden dissenter's opinions are becoming more evident in investor-state dispute settlement (ISDS); there remains a controversy over the legal foundation, functions, and system effects. Based on recent empirical research results and reforms by the United Nations Commission on International Trade Law (UNCITRAL)’s Working Group III under this background, this paper argues that because the issue of dissenting opinions has not been solved as a whole, it should also be traced back to some structural problems such as party nomination arrangements and the absence of legal precedents for trial, which are conducive to tactical decisions made during trials. The three regulatory pathways assessed were the 2023 UNCITRAL/ICSID Code of Conduct for Arbitrators, an ongoing appeal process, and the proposed Multilateral Investment Court. Therefore, this paper puts forward a step-by-step regulatory system based on these measures and designs it to fit with the pace of reform goals.Dissenting Opinions,Investor-State Dispute Settlement Mechanism,Party-Appointed Arbitrators, ISDS Reform,Appellate Mechanism,Multilateral Investment Court

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