A ruling tossing OxyContin maker Purdue Pharma's bankruptcy settlement could tee up a new issue for the U.S. Supreme Court and spur other judges to more closely scrutinize non-debtor releases, a controversial mechanism that shields third parties in Chapter 11 proceedings from liability.

On Thursday, U.S. District Judge Colleen McMahon of the Southern District of New York vacated Purdue Pharma's $4.3 billion bankruptcy settlement, finding its inclusion of a release protecting the Sackler family from civil lawsuits related to the opioid crisis was not authorized by the U.S. Bankruptcy Code, nor settled law in the U.S. Court of Appeals for the Second Circuit. The question of whether courts can grant such releases has "split the federal circuits for decades" and "hovered over bankruptcy law for thirty-five years," McMahon wrote.