Commercial brokers, landlords sue CoStar over rental data monopoly

Commercial landlords and brokers filed a class-action lawsuit against CoStar Inc., alleging it facilitated a hub-and-spoke conspiracy by collecting and redistributing confidential lease data, enabling competitors to collude on pricing and violating the Sherman Act. The lawsuit claims CoStar's data monopoly allowed brokers and landlords to exchange sensitive rental information, leading to supra-competitive rents.