We know that composers borrowed from each other, particularly in the Renaissance and Baroque era (for example, each had copies of Vivaldi concerti and Pergolesi’s Stabat Mater).
But what about now…?
Here are two examples of pop artists from the mid-1970s who used themes from Classical compositions without realising they were still in copyright.
The first is ‘All by myself’ by Eric Carmen, beloved especially by fans of Bridget Jones:
Carmen used the clarinet solo/main melody from the slow movement (Adagio sostenuto) in Rachmaninov’s Piano Concerto No.2:
“Rachmaninoff’s music was in the public domain in the United States at that time, so Carmen thought no copyright existed on it, but it was still protected outside the U.S. subsequent to the release of the album. He was later contacted by the Rachmaninoff estate and informed that it was protected.[8] An agreement was reached in which the estate would receive 12 percent of the royalties from “All by Myself” as well as from “Never Gonna Fall in Love Again”, which was based on the third movement from Rachmaninoff’s Symphony No. 2“
https://en.wikipedia.org/wiki/All_by_Myself#Background_and_composition
You can hear the original here:
The second is less well-known – in 1974, the group First Class released the following – a sort of massively orchestral Beatles / Beach Boys style Californian pop song:
What they didn’t know was that the melody they used (the ‘swan’ or ‘Thor’s hammer’ theme from the last movement of Sibelius’s Fifth Symphony heard in the French horns) was still in copyright as he’d only died in 1957 and copyright lasts for 70 years.
The estate of Jean Sibelius filed a lawsuit against the song’s writers, for infringing on the copyright of the Sibelius piece. The case was settled out of court, with the Sibelius estate receiving half of the song’s proceeds…!
Here’s the original Sibelius – to be fair, both his and that by First Class are total bangers:
The Listening Project Blog 