The Catalog of Copyright Entries is the U.S. Copyright Office’s official publication of copyright registrations and renewals, organized into categories of works. Part I includes registrations for books and pamphlets, including serials and contributions to periodicals. For books registered from January 1, 1978 to the present, the Copyright Office maintains a searchable database that can be searched online at https://www.copyright.gov/records. For books registered before 1978, the Catalog of Copyright Entries can be manually searched. Hard copies can be found at the Copyright Office located in the Library of Congress, James Madison Memorial Building, 101 Independence Ave SE, Washington, DC 20559-6000, and at a number of different libraries throughout the U.S., including Stanford, University of Michigan and University of California.
In order to provide Rightsholders with another mechanism for confirming whether books were registered with the Copyright Office before 1978, Google has scanned 91 volumes of the U.S. Copyright Office Catalog of Copyright Entries (including works registered from 1923 up to 1978) and made those volumes searchable online through Google Books. In determining the registration status of your work, you may want to check both the Copyright Office’s online database and Google’s searchable scans.
There are two ways to search Google's scans of the volumes of the Catalog of Copyright Entries. You can search over all 91 volumes that have been scanned, or you can search over individual volumes covering registrations in or around a particular year. Many times, books were registered shortly after publication (within a year or two), so the book's year of publication could be a good starting point for searching individual volumes covering a year.
You should note that the lack of results for a search of these volumes does not necessarily mean the work for which you are searching was not registered with the Copyright Office. Works may have been registered later than the year of publication (including registration after 1977, which would then be accessible through the Copyright Office's online database), and they may have been registered under other titles or as part of a larger work. In addition, because the current technology available to scan books is not perfect, it is possible that a search of these digital copies might not detect particular words that appeared in the original volumes.
Here are some tips for your searches:
Full library allowing you to view or search through copies of all scanned volumes of pre-1978 Catalog of Copyright Entries.
Type your search term (for example, title and/or author name) into this search box and then click the "Search" button. The search results will include a snippet from each of the scanned volumes of the Catalog in which your search term was detected. When you click on each snippet of text displaying your search term, a full view of the corresponding page in that volume will be displayed, with each location of your search term on that page highlighted. Your search results may include multiple pages in a single volume. You can quickly review the results within a volume by clicking on the “previous”, “next” or “view all” links in the yellow bar at the top of these search results pages. Clicking “view all” will allow you to see partial views of all the pages in a volume on which your search term was detected. You can then click on each link to a page to see the entirety of that page, and then find the search term, which will be highlighted. If necessary, add additional search terms to the above search box to narrow your search.
To view individual volumes, locate the applicable range of registration dates below and click on the Catalog of Copyright Entries volume that is most likely to contain the book for which you are searching, based on the date you believe the book was registered. Type your search term (for example, title and/or author name) into the "search in this book" search box on the left-hand side of the screen and then click the "Go" button. The search results will list all pages on which your search term was detected within the volume searched. When you click on each snippet of text displaying your search term, a full view of the corresponding page in that volume will be displayed, with each location of your search term on that page highlighted. You can quickly review the results within that volume by clicking on the “previous”, “next” or “view all” links in the yellow bar at the top of these search results pages. Clicking “view all” will allow you to see partial views of all of the pages in the volume on which your search term was detected. You can then click on each link to a page to see the entirety of that page, and thereby find the search term, which will be highlighted. If necessary, add additional search terms to narrow your search within that volume. To broaden your search, you should perform the same searches in volumes covering years in or around the year in which you believe the book was registered.