Implementing group content substitution in media works

A classification method and system for possible content alteration of a media work may include criteria regarding content that is feasible for alteration. Such criteria may be maintained in records that are accessible to an interested party. Some embodiments may include a record of primary authorization rights applicable to a possible content alteration. A further embodiment feature may include a record of secondary authorization rights applicable to substitute altered content incorporated in a derivative version. Various techniques may be used to incorporate substitute altered content in a derivative version of the media work in accordance with applicable substitution guidelines.