Whether extratextual information such as historical context and contemporary domestic law should be used to interpret treaty language, and whether the New York Convention applies to arbitration agreements involving sovereign nations acting in their sovereign capacity

QUESTIONS PRESENTED The New York Convention applies to arbitration awards “arising out of differences between persons, whether physical or legal.” The word “person” in ordinary English does not encompass a sovereign, and certainly not a sovereign acting in its sovereign capacity (as opposed to a government entity participating in markets in a private-law capacity). Meanwhile, at the time of the Convention’s adoption (in 1958), only some countries had recently begun exposing foreign government bodies to suit in court, and only for private-law activities. No country anywhere had even contemplated stripping a sovereign of immunity for cases arising from its sovereign conduct. Yet the D.C. Circuit holds that the Convention mandates judicial enforcement of arbitration awards against sovereign nations for cases arising solely from their roles as sovereigns—here, Nigeria’s sovereign obligations under a treaty with China and under public international law. The D.C. Circuit did so by refusing to adhere to this Court’s precedents on the meaning of “person”—on a theory that they address only domestic law—and ignoring the context in which the Convention was negotiated. This case thus presents two related questions. (1) Whether, for interpreting the intentions of the treaty parties regarding a word like “person,” extratextual information such as historical context and contemporary domestic law is a material input in parallel with the textual analysis; and (2) Whether the New York Convention applies for arbitration agreements governing a dispute with a sovereign nation arising out of its role as a sovereign.