The original title was to be "Superman vs. Superman". The producers of
Kramer vs. Kramer (1979) threatened a lawsuit over the similarity however, and refused to believe the Salkinds' explanation that it was intended as a play on the various "Superman vs..." comic stories and not Kramer vs. Kramer. Eventually
Pierre Spengler suggested that "Superman III" would be a more sensible title anyway, and the issue was dropped.
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