Nationality plays a vital role in the field of investor-state arbitration. Most investment treaties require that, to benefit from treaty protection, an investor must be a national of the home state. Yet, the determination of nationality for investment treaty purposes can be particularly complex, raising a number of unresolved questions of considerable practical importance. One of these questions is whether investors who hold the nationality of both state parties to an investment treaty (i.e., dual nationals) are entitled to sue their own home state where the treaty is silent on the issue of dual nationality. This contribution contends that, when faced with a claim of this nature, arbitral tribunals should apply the well-established customary rule of dominant and effective nationality, and uphold jurisdiction only if the investor maintains a stronger connection with its home state.

中文翻译：

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双重国民在投资条约下的索赔：投资者有权起诉自己的国家吗？

国籍在投资者-国家仲裁领域发挥着至关重要的作用。大多数投资条约要求，要从条约保护中受益，投资者必须是母国的国民。然而，为投资条约目的确定国籍可能特别复杂，引发了许多具有重大实际意义的未解决问题。其中一个问题是，持有投资条约缔约国双方国籍的投资者（即双重国民）是否有权在条约未就双重国籍问题提起诉讼的情况下起诉自己的母国。该文稿认为，当面临这种性质的索赔时，仲裁庭应适用已确立的主要和有效国籍的习惯规则，