Q: "I have recently completed a textbook, and am searching for a publisher. Should I have the book copyrighted?"
A: Mary Ellen Lepionka, author of Writing & Developing Your College Textbook: A Comprehensive Guide:
"You can, or the publisher can do that for you in your name. The publisher typically pays the fee and sends two finished copies to the Library of Congress when the book is out. Request that the publisher register the copyright in your name, which is normal unless you have permanently assigned copyright to the publisher. My understanding is that in signing the publishing contract you do assign exclusive copyright use to the publisher (hopefully for a specified time rather than indefinitely), after which rights can revert to the author. However, an original work is ultimately, automatically, the property of its author or creator, which is a separate function from granting rights.