...YOU are the initial copyright holder unless you've transferred your rights or you've made the work for hire.
U.S. copyright law grants the following rights to a copyright owner, and registration is not necessary to receive these rights:
Joint and Collective Works. Collaboration is common in many fields, and it has significant implications for your rights and options as a copyright holder. Nolo's "Joint Copyright Ownership Versus Collective Work: Understanding the Difference" is a good introduction to these concepts. See also sections 505 Joint Works and 509 Collective Works and Contributions to Collective Works of the Compendium of U.S. Copyright Office Practices (3d ed. 2021).
Works for Hire. You may not be the copyright holder if the work was created within the scope of your employment. Circular 30 from the U.S. Copyright Office explains works for hire, and it is important to understand your specific employer's policies as well.
...YOU have the ability to give these rights away or to share them with others. Of course, others are still able to employ exceptions to use your work without your permission.
Assigning your rights matters. If you transfer copyright without retaining any rights, you must request permission from the holder, unless the use falls within one of the exemptions in copyright law. This means you may not be able to place the work on course web sites, copy it for students or colleagues, deposit the work in a public online archive, or reuse portions in a subsequent work.
Transferring copyright doesn't have to be all or nothing. Copyright is a bundle of several rights. The law allows you to transfer copyright while still keeping rights for yourself and others. The terms of your publication agreement determine what rights you give to your publisher, and what rights you retain.
Content in this guide has been reused and adapted with permission from Kristen Hoffman of Seattle Pacific University Libraries. The original guide is available at https://spu.libguides.com/author_copyright.