Thinking Out Loud has turned into a wedding favourite with more than a billion plays on YouTube and the first song to hit 500 million streams on Spotify. It is a hit track on his album X, which has sold more than 15 million copies.
This is the fifth time Ed has been accused of copying songs from other artists.
Last year, Real Housewives Of Atlanta star Kandi Burruss was given a writing credit on Sheeran's Shape of You, when the US copyright website ASCAP (American Society of Composers, Authors and Publishers) amended its listing for the chart topping song after countless listeners pointed out the similarities between it and TLC's 1999 hit No Scrubs.
The family of Ed Townsend - who wrote Let's Get It On - previously accused the singer of ripping off the Marvin Gaye hit when he wrote Thinking Out Loud.
In 2016 Martin Harrington and Thomas Leonard - who wrote X Factor star Matt Cardle's 2012 song Amazing - made a similar claim, suing him for $20 million over Sheeran's song, Photograph.
While more recently Ed, who recorded and co-wrote The Rest Of Our Life with Tim McGraw and Faith Hill, was reportedly sued for US$5 million for their hit.
Australians Sean Carey and Beau Golden alleged that the song is "blatantly copied" from one they wrote in 2014 called When I Found You.
Just earlier this year, Marvin Gaye's family were awarded US$5.3 million after a split decision from a three-judge panel, the 9th US Circuit Court of Appeals, who said Robin Thicke and Pharrell Williams' 2013 Blurred Lines song is illegally copied from the late soul singer's Got to Give it Up.