Brown Shoe Company, Inc. (Brown) (defendant) was the third-largest seller of shoes in the United States and a leading manufacturer and retailer of shoes. Brown merged with the G.R. Kinney Company, Inc. (Kinney), the eighth-largest seller of shoes and owner of over 350 retail locations. Kinney also manufactured shoes. The federal government brought an antitrust action to block the merger, arguing that the merger would produce significant anticompetitive effects in the national wholesale and retail shoe markets. In district court, Brown argued that the market for shoes was robust and would remain competitive in the wake of the merger, because Brown’s total post-merger market share was not significant. The district court disagreed, however, and granted the federal government’s motion to disband the merger. Brown appealed the decision.