A data processing apparatus for reproducing a plurality of object streams having predetermined information severally, which apparatus is provided with an IPMP information extraction circuit (54) for extracting hierarchical management information for controlling the permission and inhibition of the usage of each object from input data, a usage status check circuit (56) for judging whether the usage of an upper level object of a subjected object is prohibited or not in accordance with the IPMP information extracted by the IPMP information extraction circuit (54), and a control information extraction circuit (58) for controlling the data processing apparatus to prohibit the usage of the subjected object if the usage of the upper level object of the subjected object is prohibited in accordance with a judgment result by the usage status check circuit (56).