Initially the author(s)/creator(s) own the copyright to their work, however many publishers ask the author/creator to sign over most or all their rights to them.
As an author, you can retain rights to your work, but you have to negotiate with the publishers when the materials are submitted or accepted for publication.
Many Duke faculty publications, especially older works, are not owned by the author.
In some cases the institution may own the work, if an employee (not a faculty member) did the work as part of their job. This is called "work for hire" so often manuals, Web pages, etc. are owned by the institution and not the individual creator.
Under the law, copyright holders are given the following exclusive rights, which means that others cannot use these rights without seeking permission:
Authors can give up their rights and often do to publishers who then become the copyright holder. Unless the author retains certain rights, they cannot distribute or even post a PDF or copy of their work without seeking permission from the publisher.