The copyright infringement lawsuit was filed by Martin Harrington, a songwriter and producer, and Thomas Leonard, a songwriter signed to Harrington's company HaloSongs, in federal court in the Central District of California.
The two musicians allege Sheeran's ballad Photograph, released as a single in 2015, has the same musical composition to their song Amazing, which they said they wrote in 2009.
Other named defendants include Snow Patrol's Johnny McDaid, credited as a co-writer of Photograph, as well as units of Sony/ATV Music Publishing, Warner Music Group and its subsidiary, Atlantic Recording Corporation.
Representatives for Sheeran, McDaid, Sony Music, Warner Music and Atlantic did not immediately respond to Reuters' requests for comment on Wednesday.
Harrington and Leonard are seeking a jury trial and damages in excess of $20 million, as well as royalties from the song.
In documents that include musical note comparison and chord breakdowns of the two songs, Harrington and Leonard claim the chorus of Sheeran's Photograph shares 39 identical notes with Amazing, saying the similarities are "instantly recognisable to the ordinary observer."
The documents say that Photograph has sold more than 3.5 million copies worldwide, and most recently was featured prominently in romantic drama movie Me Before You, released last week, as well as trailers for the film.
