CICS can create channels and containers for its own use, and pass them to user programs. In some cases CICS marks these containers as read only, so that the user program cannot modify data which CICS needs on return from the user program.
User programs cannot create read only containers.
You cannot overwrite, move, or delete a read only container. Thus, if you specify a read only container on a PUT CONTAINER, MOVE CONTAINER, or DELETE CONTAINER command an INVREQ condition occurs.