On Dec. 1, 2023, the U.S. Court of Appeals for the Fourth Circuit reversed a bid-rigging conviction of a former aluminum products manufacturing company executive, holding that the alleged conspiracy should be analyzed under the more permissive rule of reason rather than the per se standard because of the supplier-customer relationship between the alleged conspiring bidders. The Fourth Circuit declined to reconsider its panel ruling on Feb. 16 despite the Department of Justice's (DOJ) arguments that the court's decision is inconsistent with long-standing Sherman Act precedent. Although the DOJ may still seek U.S. Supreme Court review of the Fourth Circuit's decision, if upheld the decision represents a significant restriction on the DOJ's prosecutions for alleged collusive conduct between parties when there is any type of vertical business relationship present.