I found an error in the database. Can you fix it?

It depends. The database is based on the Copyright Office's Catalog of Copyright Entries (CCE) publication. If the error that you've found is a discrepancy between the database and the CCE, then yes, we will make the correction to our database. Please use the "Feedback" button above to submit the change request. If the error is in the CCE itself, we won't make a change, in order to retain that compatibility with the original.

The Copyright Renewal Database only includes "Class A" renewals. What does that mean? What other classifications of renewals are there?

During the period of publication of the Catalog of Copyright Entries, the Copyright Office used letter codes to designate the different types of material that were granted copyright. Type A refers to books. You can find the full list of classification types by looking back at digitized versions of the CCE, like this one: https://books.google.com/books?id=ZB0hAQAAIAAJ&printsec=frontcover&source-gbsgesummary_r&cad=0#v=onepage&q&f=false. Scroll to page vi.

What do the codes next to the names of the renewing entities mean?

Codes tell you the relationship between the renewing entity and the author. A = Author, W = Widow, PWH = Proprietor of a Work Made for Hire, etc. The commonly used relationship codes can be found in digitized versions of the CCE, like this one: https://books.google.com/books?id=ZB0hAQAAIAAJ&printsec=frontcover&source=gbsgesummary_r&cad=0#v=onepage&q&f=false Scrolle to page viii-ix.