portion 17 a further in the case that it is not desired to mark the disc take out history such as a movement of the disc between the disc cartridges the disc is taken out by removing the locking hook 6 a without breaking the locking cancellation preventing member 16 a as shown in fig2 c a description will be given of a method of removing the locking hook 6 a without breaking the locking cancellation preventing member 16 a with reference to fig3 an opening portion 19 a which is small enough that the user can not operate the locking hook 6 a by a finger is provided between the locking cancellation preventing member 16 a and the disc cartridge 1 the locking hook 6 a is moved by inserting the locking cancellation member 18 a from the opening portion 19 a as shown in fig3 b thereby being removed from the locking hole 7 a a locking cancellation member 18 a is for example provided near the disc insertion and removal portion of the disc cartridge in a destination for the disc so that a cancellation of the locking and a moving operation of the disc can be both performed by pressing the disc cartridge 1 in accordance with the present invention next a second embodiment in accordance with the present invention.