The attitude of copyright holders toward incorporating fan fiction into the canon varies. Some copyright holders, such as the BBC in the case of "Doctor Who", have mechanisms to allow for unsolicited submissions of stories into the official canon, and it is also the case that the writers of canon stories have sometimes been recruited from the ranks of fan fiction writers. In the case of the "Doctor Who" novels published by Virgin Books, once the BBC reclaimed the license to publish novels regarding the Doctor, many readers immediately categorized all the Virgin New Adventures as non-canonical fan fiction.