One of the love songs in the play, "Sammy", became a sensation. It was sung by the fetching actress Lotta Faust, who would single out a male member of the audience and embarrass him by singing it specifically to him. Other theaters began to copy this technique.
Hamlin (the producer of The Wizard of Oz) and Sol Bloom (the writer of the song "Sammy") sued the owners and managers of a rival theater company because their actress, Fay Templeton, imitated Lotta Faust singing "Sammy". [The case was Bloom & Hamlin v. Nixon et al. (No. 18, Circuit Court, E.D. Pennsylvania, 125 F. 977) . ] In this case, Templeton only sang the chorus, rather than the entire song. The court decided that this was permissible fair use, because the actress was not simply singing the song, but rather mimicking Lotta Faust, and the song (or part of it) was an essential part of the mimickry.
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Lotta Faust