A creator who has transferred her rights to another entity, such as a publisher or record label, may terminate the grant in certain conditions. These conditions are covered under Section 203 of the Copyright Act, and are outlined in the pages indicated on the bar to the right.
For more information on termination, see "A Second Bite of the Apple: A Guide to Terminating Transfers Under Section 203 of the Copyright Act" and the Creative Commons' Termination of Transfer Tool.