This article addresses jurisdiction of arbitral tribunals constituted under international investment agreements over sovereign bond related claims brought in class-action style proceedings following the decision in Abaclat v. Argentina. The year 2011 was one of impending sovereign defaults, with the United States, Greece and, to a lesser extent, Italy, Portugal, and Spain, perceived to be at the brink of default. In the case of the United States in particular, the specter of default had every appearance of populist, political maneuvering rather than economic extremis. The Greek saga, similarly, at times resembled a study in political theatre rather than sober economic analysis, though there is no denying the dire seriousness of that country’s economic troubles.