QUESTION: When should I copyright my novel?
According to US copyright law, your book was copyrighted the moment you put something on the page.
If, however, you want to file an official copyright with the US Copyright Office, the answer is different for your publishing choices.
If you want to be published by a traditional publisher, aka the conglomerates mainly in NYC, you shouldn’t do an official copyright because it makes you look like an amateur. And, if they buy it, it will most likely will be copyrighted again because it will have been changed drastically in rewrites. In most cases, the publisher will do the copyright for you. Check your contract on this question and make dang sure the copyright is in YOUR name.
Some small publishers expect their authors to file their own copyright. Do this as soon as you have the published version of your novel. It can be done before the book reaches the shelves.
If you are self-publishing, copyright it as soon as you have the final version of your book. An official copyright is a good thing because you won’t be able to sue someone for plagiarism or downright theft in an American court without that official copyright notice.
Here’s a link to the Copyright Registration form.