Most lawsuits don’t present American judges with the choice of whether to defer to a foreign court ruling. But that’s the unique situation that arose in a KBR Inc. subsidiary’s contract dispute with Mexico’s state-owned oil company, Pemex.

On Tuesday, a legal team helmed by Richard Marooney Jr. of King & Spalding and Paul Clement of Bancroft PLLC secured an appeals court ruling for their client, KBR’s Mexican unit COMMISA, that should put Pemex on the hook for more than $465 million.