Only supported in WebSphere MQ for z/OS.
Queue-sharing groups are not strictly objects, but are mentioned here for convenience.
Queue managers that can access the same set of shared queues form a group called a queue-sharing group (QSG), and they communicate with each other by means of a coupling facility (CF) that stores the shared queues. A shared queue is a type of local queue whose messages can be accessed by one or more queue managers that are in a queue-sharing group. (This is not the same as a queue being "shared" by more than one application, via the same queue manager.) See WebSphere MQ for z/OS Concepts and Planning Guide for a full discussion of shared queues and queue-sharing groups.