国际投资仲裁中的东道国反请求问题研究

国际投资仲裁主要以投资者与东道国之间的仲裁为主，投资者可以根据母国与东道国签订的双边投资条约向解决投资争端国际中心（ICSID）请求仲裁，或者根据UNCITRAL仲裁规则或其他仲裁规则进行临时仲裁。晚近投资者与东道国的仲裁实践中，部分东道国提出反请求，但或被仲裁庭以没有管辖权为由拒绝审理，或因反请求的理由不成立而无法起到应有的作用。实际上，《解决国家与他国国民之间投资争议公约》、ICSID仲裁规则和UNCITRAL仲裁规则都允许东道国提起反请求，即原则上仲裁庭对反请求有管辖权。个案中，只要涉案的双边投资条约中的争端解决条款对“争议”（disputes）的定义足够宽泛，不局限于东道国义务，那么东道国便可能提起与原请求有一定联系的反请求。实体法层面，东道国反请求的法律基础可能是投资者违反相关的国际法、违反与投资相关的投资合同，或者违反在投资条约中明确提及的东道国国内法等。明确东道国反请求涉及的程序和实体问题，不仅可以为东道国在国际投资仲裁中行使应有的权利、维护本国根本利益和社会公共利益提供清晰的进路，还可以促进国际投资仲裁体制向更加中立、权威的方向发展。

International investment arbitration mainly consists investor-state arbitration. Investors can file for arbitration in International Center for Settlement of Investment Dispute （ICSID） or under arbitration rules like UNCITRAL Arbitration Rules, based on the Bilateral Investment Treaty （BIT） between their home countries and the host states. In the recent practice of investor-state arbitration, some host states raised counterclaims, but were rejected by international tribunals for falling out of their jurisdiction, or simply because the counterclaims were baseless. In fact, the Convention on the Settlement of Investment Dispute between States and Nationals of Other States, the ICSID Arbitration Rules and the UNCITRAL Arbitration Rules all permit the respondent state to file a counterclaim, that is, in principle, the international arbitral tribunal have jurisdiction over the counterclaims. In a particular case, as long as the definition of ＂disputes＂ contained in the dispute settlement provisions of the relevant BITs is broad enough, for example, is not limited to obligations of the host state, then the respondent state may be able to file a counterclaim which has certain connection with the primary claim. As for substantive request, counterclaims may be based upon investors＇ violation of international law, of relevant investment contracts, or the domestic law of the host state which is clearly referred in the BIT. Study on jurisdictional and merits issues of respondent states＇ counterclaims can not only provide legal access for respondent states to exercise their rights and safeguard their essential interests and public interests, but also facilitate the international investment arbitration system to a more neutral and authoritative direction.