Many observers over the years have commented on the various tactics employed by issuers of corporate debt seeking to restructure or repurchase their securities and the potentially coercive effects of these actions on bondholders. In response to issuer actions of this sort, large bondholders of a particular security often band together in groups or committees to try and negotiate collectively with the issuer and obtain more favorable terms. In some circumstances, these collaborations bring together fi rms that may be considered competitors in some aspects of their businesses and have on occasion been challenged as unlawful price-fixing agreements or group boycotts under section 1 of the Sherman Act. This article reviews the opinions in those cases and discusses the antitrust implications of collective action by bondholders or their representatives in dealings with a common issuer.