THE Script are suing James Arthur for copyright infringement over alleged similarities between the Irish band's hit The Man Who Can't Be Moved and the British singer's 2016 comeback single Say You Won't Let Go.
According to reports in the US, the group have filed a lawsuit at Los Angeles Superior Court against Arthur, his co-writers and a number of publishing companies.
Arthur, who shot to fame after winning the ninth series of The X Factor in 2012, has denied the claim.
The Script - comprised of Dublin trio Danny O'Donoghue, Mark Sheehan and Glen Power - released The Man Who Can't Be Moved as a single in 2008.
The band claim Arthur's Say You Won't Let Go single has generated $20m in revenue and statutory damages are being sought.
The Script's lawyers have requested accounts on all revenue generated from Arthur's song and that legal action be heard before a jury.
The lawsuit also alleges that Arthur approached the group with a view to collaborating in 2014 but was turned down.
The Script's attorney, Richard Busch, previously represented the Marvin Gaye estate in its successful copyright infringement lawsuit against Robin Thicke and Pharrell Williams for their 2013 hit Blurred Lines.
Danny O'Donoghue and Mark Sheehan co-wrote The Man Who Can't Be Moved with Andrew Frampton and Stephen Kipner, with the song appearing on the band's eponymous debut album a decade ago.