The group claims that "Uptown Funk" is too similar to "Funk You Up."
The 1979 single was only the third rap song ever to hit the Billboard Top 50 chart. "Uptown Funk" has "significant and substantially similar compositional elements" of 'Funk You Up,'" according to court documents obtained by TMZ.
Sequence is seeking a jury trial and unspecified damages from Mars and Ronson.
In a 2014 article on the influences of "Uptown Funk," Billboard listed "Funk You Up" as one of the tracks Ronson and Mars referenced.
Ronson and Mars have faced several lawsuits over "Uptown Funk," which now officially has nine different songwriters listed. In April 2015, Music Week reported that Lonnie Simmons, Ronnie Wilson, Charles Wilson, Robert Wilson and Rudolph Taylor were all added to the credits because it includes references to The Gap Band's 1979 hit "Oops Up Side Your Head."
"Uptown Funk" was featured on Ronson's 2015 album Uptown Special and is the biggest hit of Mars' career. The YouTube video has been seen over 2.8 billion times and the song has sold 7.8 million copies as of September 2017.