The provisions in the 1976 Copyright Act governing termination of grants of interests in copyrights can be found at 17 U.S.C. § 203 and 17 U.S.C.  § 304.  The provisions of Section 203 govern grants made after January 1, 1978 and those in Section 304(c) govern pre-1978 grants.   There is a great deal of overlap between the provisions governing pre- and post-1/1/78 grants, but there are some important differences, which will be covered below and in posts to come.  

For both pre- and post-1/1/78 grants, any transfer of an interest in a copyright is subject to possible termination.   This means that an assignment of the entire copyright interest or a part thereof can be terminated, as can a license of a more limited copyright interest (e.g., a license from an author to a book publishing company or from a screenwriter to a motion picture company).  Both exclusive and non-exclusive licenses may be terminated.   In short, a creator's assignment of his entire interest in the copyright in a work may be subject to termination.  And so will a grant of a much more limited license (e.g., an author's grant of the audio book rights in her novel).

For grants made prior to 1/1/78, any grant made by the author of the work or, if the author is no longer living, by certain successors as described in the Copyright Act may be terminated.  For post-1/1/78 grants only those made by the author can be terminated.  

For both pre- and post-1/1/78 grants, any transfer made by will is not subject to termination.  Nor is a grant in a work made for hire (a subject that will be covered in some considerable detail in a post to come).

Next up:  The critical question of timing:  When is a grant subject to termination?