The "Lupin III" creator,
Monkey Punch, did not seek permission from
Maurice Leblanc's estate to use the name of Arsène Lupin, and at that time Japan did not enforce trade copyrights. This led to copyright issues once Lupin's popularity spread to North America and Europe, (the name was still permitted in Japan however), and in English translations of the film, the protagonist was known as either "Wolf" (the direct meaning of "Lupin") or "Rupan" (the Japanese pronunciation of the word)
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