A U.S. judge dismissed a lawsuit claiming that the hit CBS comedy The Big Bang Theory borrowed lyrics without permission for “Soft Kitty,” a song used on several episodes of the show.
The lawsuit had been brought in December 2015 by the daughters of Edith Newlin, a New Hampshire nursery school teacher who had written the nearly identical poem “Warm Kitty” in the 1930s.
But in a decision posted on Tuesday, U.S. District Judge Naomi Reice Buchwald in Manhattan said the plaintiffs, Ellen Newlin Chase and Margaret Chase Perry, failed to show they held a copyright on their mother’s lyrics, and deserved damages.
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Lawyers for the plaintiffs did not immediately respond on Wednesday to requests for comment. Spokesmen for CBS (cbs) and Time Warner (twx), whose Warner Bros. Entertainment unit helps produce the show, declined to comment.
The complaint said Newlin wrote “Warm Kitty” with the words “Warm kitty, soft kitty, little ball of fur; Sleepy kitty, happy kitty, Purr! Purr! Purr!” and allowed the words to be used in the 1937 book “Songs for the Nursery School,” published by Willis Music Co.
“Soft Kitty,” often sung to Jim Parsons’ character Sheldon Cooper to soothe him in The Big Bang Theory, uses identical words with small changes in order, as in the opening line “Soft kitty, warm kitty,” the complaint said.
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But the judge said that, under a federal copyright provision that was “hardly a model of clarity,” Willis Music’s renewal in 1964 of its registration for “Songs for the Nursery School” did not also renew Newlin’s copyright for “Warm Kitty.”
Edith Newlin died in 2004 at the age of 99. The plaintiffs said they did not know about “Soft Kitty” until 2014 when Ellen Newlin Chase saw a blog post about the song and The Big Bang Theory, which she had never watched.
The Big Bang Theory, premiered in 2007 and has been one of the highest-rated U.S. television shows for several years.