Stairway to Heaven is one of the greatest rock songs hit by Led Zeppelin. The band was sued for copyright in 2014 over claims they had stolen the opening riff from the song Taurus by a US band called Spirit. Zeppelin won the case in 2016 but was later revived by an appeal in 2018. The 9th US Circuit Court of Appeals upheld the original verdict in March 2020 and the US Supreme Court has declined to hear the case putting an ending to the copyright battle.
Source: https://www.bbc.com/news/entertainment-arts-54423922