UniteSync does not register songs with the Copyright Office. As per copyright law, the ownership of a composition belongs to the composer from the moment it is fixed in a tangible medium, such as being written down or recorded. However, registering the copyright with the Library of Congress can make this ownership a public record, providing the composer/author with additional benefits. In other words, if a work is registered with the copyright office, the author/composer has a stronger claim against infringements and can receive better damage compensation as a result of infringement.
To register your copyright, you can complete the registration process online at https://www.copyright.gov/registration/. The PA form (Work of the Performing Arts) is used to register a composition that includes lyrics and music. On the other hand, the SR form (Sound Recording) is used to register the master or audio/sound recording only.