This invention manages temporary storage of content data according to guidelines. According to this invention, when temporary storage of a recording transport stream TS3 which is allowed to be temporarily stored in a recording medium so as to be reproducible only within a temporary storage allowable time is managed, a reproducible start point indicating a start point from which the recording transport stream TS3 can be reproduced is associated with a first time stamp out of the time stamps of the GOPs of the recording transport stream TS3, and every time when a period from a time stamp associated with the reproducible start point to the current time reaches a temporary storage allowable time, the reproducible start point is re-associated to another time stamp following the time stamp, so that an overtime part of the recording transport stream TS3 can be removed from a reproducible range so as to easily and correctly disable its reproduction, thus being capable of easily and correctly managing the temporary storage of the recording transport stream TS3.