Former U.S. solicitors general Theodore Olson and Donald Verrilli Jr. are set to square off before the U.S Supreme Court in October, to resolve a complex dispute over the status of an oversight board, established by Congress in 2016 to help Puerto Rico recover from a devastating financial crisis.

Olson, partner at Gibson, Dunn & Crutcher, and Verrilli, partner at Munger, Tolles & Olson, are counsel of record for the main parties in the dispute. They are veteran advocates who have argued on the same and opposite sides of numerous appellate cases. Current solicitor general Noel Francisco is also likely to argue, though that is not certain.