Great Regulars: Books that are still in copyright

are a more complicated challenge for the would-be writer of prequels and sequels. This is partly because a lot of money is sometimes at stake. The Mitchell estate was so fussy about protecting "Gone With the Wind" because the franchise is a gold mine. Alexandra Ripley's "Scarlett," an authorized sequel, was a huge best seller in 1991, even though the critics sniffed at it. Living authors, moreover, are understandably attached to their characters and creations and may not want to think of them as demented, say, or having problems with bladder control. Where do you draw the line between critique or parody and outright exploitation?

from Charles McGrath: The New York Times: The Sincerest Form of Lawsuit Bait

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