No. In general, registration is voluntary. Copyright exists from the moment the work is created. You will have to register, however, if you wish to bring a lawsuit for infringement of a U.S. work. Holding a registered copyright can be useful in the event of litigation and it is encouraged by Destiny House Publishing.
Both published and unpublished works are considered copyrighted.
If you register your work with the copyright office, this registration can be used in court should a lawsuit occur. It provides protection for your work if someone infringes or challenges your copyright.
If you believe that someone else has infringed your copyright, you should consult an attorney. You can file a civil suit; a criminal investigation may be appropriate.
Keep in mind that US copyright law doesn’t cover all types of works. Titles, names, slogans, and concepts are examples of materials that are not protected by copyright. You are responsible for knowing whether your work is a protected type.
Remember that although the US has copyright relations with many nations across the world, not all countries honor the US’s copyright laws.
Note: Please keep in mind that Destiny House Publishing does not offer legal advice or protection. Following copyright laws is the responsibility of you as a DHP author because you retain the copyright to your work when it is published on Destiny House Publishing. For more information, check out the United States Copyright Office