Several sources are reporting that IBM is facing an antitrust inquiry from the US Department of Justice due to a supposed refusal to issue mainframe OS licenses to competitors. "Part of CCIA's complaint stems from the tech giant's treatment of former competitor Platform Solutions. IBM had little competition in the mainframe market when Platform Solutions, early this decade, began work on servers that could mimic the behavior of more expensive IBM mainframes, CCIA said. Platform Solutions, based on past mainframe agreements between IBM and the DOJ, requested copies of IBM's OS and technical information under a licensing agreement. IBM declined to grant Platform Solutions a license and prohibited customers from transferring IBM software licenses to Platform Solutions machines, said CCIA, which has members that are potential competitors of IBM."