The heirs to "Warm Kitty" writer Edith Newlin have filed a lawsuit against the producers of The Big Bang Theory for violation of copyright, The Associated Press reports.
Newlin was a New Hampshire English teacher, who adapted the tune from a traditional English folk tune and reworked the lyrics in the 1930s.
Prior to The Big Bang Theory, versions of the song were recorded and released by Australian children's recording artist Patsy Biscoe and on Play School, the long-running Australian children's TV series.
In 2011, The Big Bang Theory started to merchandise "Soft Kitty," their fictionalized version of the song -- although it appears from the sheet music above as though that song is identical to "Warm Kitty" in its entire first verse, with the exception of swapping the order of two words.
The words and music appeared in the song book Songs for the Nursery edited by Laura Pendleton MacCarteney and published by Willis Music Co. in 1937, according to the song's Wikipedia entry; the copyright on that book was renewed in 1964.
Newlin passed away in 2004; The daughters' lawsuit, seeking unspecified damages from the show's producers and distributors, says the "Soft Kitty" lyrics have been used in their entirety on at least eight episodes of the show since March 2008.
"The 'Soft Kitty' lyrics are among the best-known and most popular aspects of The Big Bang Theory," the lawsuit alleges. "They have become a signature and emblematic feature of the show and a central part of the show's promotion."
In addition to the merchandising associated with the song, The AP notes that at least three Comic Con International panels have featured the cast and producers singing the song. Those panels are often made available on streaming services and/or as special features on home video releases.
Newlin's daughters are apparently not regular viewers of the show; they reportedly learned of the "Soft Kitty" lullaby in late 2014, while writing an article about their late mother.
The lawsuit says Warner Bros. Entertainment and the show's other producers sought permission from Willis Music Co., who published Songs for the Nursery, in 2007. The lawsuit says Willis Music authorized use of the lyrics without consulting or getting permission from Newlin's heirs, even though the book makes clear on its acknowledgement page and where the lyrics appear that Newlin was the author of and owned the copyright to the lyrics.
If that's the case, the show's producers could plausibly be penalized and then seek redress from Willis Music Co., if they believed themselves to be acting in good faith. If it's true that Newlin is listed as the copyright holder, though, it may be difficult for Warner to prove that they were unaware of the conflict.
Warner Bros. and CBS had no comments for the AP story.