of facilitating settlement.” Id. Vacatur was granted nevertheless, because the district court had erred in imposing the sanction in the first place, and because “if the sanction were removed then the way to a settlement would be clear.” Id. at 98, 100. In both Major League Baseball and Keller, the exceptional circumstances had to do with the facilitation of settlements that would obviate pending appeals. But equitable vacatur is not limited to situations that serve the convenience of appellate courts. By nature, circumstances that are “exceptional” elude such limits or classification. And Bancorp expressly envisions a situation where a judgment already mooted by settlement may nonetheless require vacatur because of exceptional circumstances. See Bancorp, 513 U.S. at 29, 115 S.Ct. 386 (<HOLDING>). The following circumstances convince us to
recognizing equitable subrogation recognizing that the determination is an equitable one holding that the allocation of response costs under  113f is an equitable determination based on the district courts discretionary selection of the appropriate equitable factors in a given case holding one example of a claim is a right to an equitable remedy that can be satisfied by an alternative right to payment holding that equitable title for property is one derived through a valid contract