Unofficial Sequels
Sometimes sequels are produced without the consent of the creator of the original work. These may be dubbed unofficial, informal, unauthorized, or illegitimate sequels. In some cases, the work is in the public domain, and there is no legal obstacle to producing sequels, for example Jean Rhys wrote Wide Sargasso Sea as a parallel to Jane Eyre. In other cases, the original creator or their heirs may assert copyrights and challenge the creators of the sequels. For example, the estate of Margaret Mitchell sued over Alice Randall's novel The Wind Done Gone, a parallel of Gone with the Wind told from the perspective of the slaves; it was successfully defended as parody. Unofficial sequels to works that are still under copyright may change the names of the characters and alter the settings in an attempt to avoid legal action.
Other examples of such unofficial sequels include:
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