English singer Edward Christopher Sheeran aka

According to legal documents, Sheeran's "Photograph" copied their song called "Amazing", written by Martin Harrington and Thomas Leonard for "X Factor" season 7 winner Matt Cardle.

And interestingly, the songwriters hired the same attorneys that won a $7.4 million judgment against Robin Thicke and Pharrell's "Blurred Lines."

They're suing for copyright infringement and seeking more than $20 million in damages, TMZ reports.