Pocket part
![An example of how pocket parts may outgrow the pockets. The ninth edition of Witkin's Summary of California Law has been superseded by a new edition because the pocket parts grew too big.](/Images/godic/202502/03/Witkin_ninth_edition_CA_law3433.jpg")
A pocket part is a special document located inside the back cover of certain hardcover legal reference books. Legal researchers consult it to ensure that the most current law is examined.
A legal reference book designed to be used with a pocket part subscription comes in the form of a sturdy hardcover book with a large pocket built into the back cover. At regular intervals (either annually or quarterly), the publisher sends out a new pocket part, which is a simple saddle-stapled pamphlet printed on cheap newsprint. The part comes with a thick card stapled or glued to one cover, and that card is inserted into the pocket to hold the pocket part inside the book which it updates. The task of regularly replacing pocket parts is one of the major chores of operating a law library.