Publication agreements often require authors to give up all or many of their intellectual property rights as a condition of publication. This may limit your ability as an author to legally distribute or reuse your work - posting your paper on your website, passing out copies to your class, or republishing a revised article as a book chapter can be disallowed in some publication agreements. However, understanding basic copyright and using tools such as the Scholarly Publishing and Academic Resources Coalition (SPARC) Author Addendum can help you work with publishers to retain as many of your rights as possible.
As an author of a work you are the copyright holder unless and until you assign all or part of you copyright to someone else. Standard publication agreements or copyright transfer agreements typically transfer more of the author's copyright to the publisher than is necessary to publish the work. Contracts are negotiable - read them careful and ask about any provisions your think are unnecessary. Attaching a SPARC Author Addendum can be any easy way to keep more of your rights - the Addendum grants the publisher a non-exclusive right to distribute the work and receive proper attribution while retaining the author's right to use the work for education and research, adapt the work, and deposit the work in an open access repository.
SPARC Author Addendum - Download and print a copy that can be filled out by hand.