What is an LCCN (Library of Congress Control Number)?

What is an LCCN (Library of Congress Control Number)?

The Library of Congress Control Number (LCCN) is a unique identification number that the Library of Congress assigns to titles that it is likely to acquire. This is not the same as a copyright registration. Librarians use the LCCN to access the associated bibliographic record in the Library of Congress’ database or to obtain information on various book titles in other databases. The publisher prints the LCCN on the back of the title page in the following manner: Library of Congress Control Number: 2001012345.
Only U.S. book publishers are eligible to obtain an LCCN. To receive an LCCN, publishers must list a U.S. place of publication on the title page or copyright page and maintain an editorial office in the country capable of answering substantive bibliographic questions.
There is no charge for registering, but the publisher must send a copy of the “best edition” of the book for which the LCCN was pre-assigned (you apply for the LCCN prior to publication) immediately upon publication to the Library of Congress. If using the U.S. Postal Service, mail to: Library of Congress, US & Publisher Liaison Division, Cataloging in Publication Program, 101 Independence Ave., S.E., Washington, DC, 20540-4320. If using a commercial shipper, send to: Library of Congress, USPL/CIP 20540-4283, 9140 East Hampton Drive, Capitol Heights, MD 20743. The “best edition” of a book is the retail paperback or hardcover version of the book.
Books published in electronic form are ineligible for an LCCN.
Should you wish to obtain an LCCN on your own, the first step is to complete the Application to Participate and obtain an account number and password, which takes one to two weeks. The application is found online. Complete information about the LCCN process can be found at http://pcn.loc.gov/pcn006.html.
A publisher may try to tell you that there is a fee for an LCCN, or that it has to charge you a fee because it needs to obtain one for each edition of your book. Don’t believe the publisher. Unlike an ISBN, the LCCN is assigned to the work itself and doesn’t change with each new edition or version. Certainly, it takes time and effort to submit the application, and it is fair for a publisher to build this into its fee. It’s not fair for a publisher to pretend that the Library of Congress charges a fee for the LCCN.