The Blu-ray BD+ licensing authority maintains a list of BD+ adopters. BD+ is the virtual machine-based programmable security component of the Blu-ray security architecture.
Since I last checked, four companies have been added to the list of adopters: Intel, Lite-On IT Corp., MIT Technology, and Quatius Ltd. have been added to the list of BD+ adopters. One company has apparently been deleted: Cheertek Inc.
Fox remains the only studio publicly listed as a content participant.