We own any fictional characters or other elements that we create when they could be protected by U.S. copyright laws. You own any fictional characters or other elements that you create when they could be protected by U.S. copyright laws.
This is a complex question that depends on facts as well as law. We cannot advise you about the facts of your situation. We can tell you some important things the law says.
Generally, a work can only be protected by U.S. copyright law if it contains a sufficient amount of original ownership.
The law does not protect:
- Ideas or concepts for a work of authorship,
- The idea for or name of a character,
- The title of a work,
- Catchphrases, or
- Stock characters, settings, or events that are common to a particular subject matter or medium.
For example Wonder Woman is protected by copyright because the character contains a sufficient amount of original ownership: she has an origin story, a costume, specific powers and tools, and other elements of originality and creativity. A character who is a woman with superpowers is not protected by copyright unless the character is sufficiently original.
The information in this answer was found in the Compendium of the U.S. Copyright Office Practices Section 101, Chapter 300, Sections 313.3(A), 313.4(H), 313.4(I), and the Glossary (3d ed. 2021). https://www.copyright.gov/comp3/chap300/ch300-copyrightable-authorship.pdf, https://www.copyright.gov/comp3/docs/glossary.pdf