Sam Smith’s “Stay With Me,” a single from his debut album In the Lonely Hour, tore up the charts when it was released in May of last year. The song peaked at #2 on the Billboard Hot 100 list, and has sold nearly 3.5 million copies to date.

There’s only one problem, though; Smith’s song sounds almost exactly like another hit song – from 26 years ago.

When “Stay With Me” was first released, attentive listeners noticed the song sounded eerily familiar to Tom Petty’s 1989 hit “I Won’t Back Down,” which Petty wrote with songwriting partner Jeff Lynne. Smith apparently agreed, because he settled a lawsuit with Petty and Lynne giving them songwriting credit on the hit as well as 25% of the song’s royalties, according to U.K. paper The Sun.

A rep for Smith said in a statement that the similarities between the songs were a “complete coincidence.”

Recently the publishers for the song I Won’t Back Down, written by Tom Petty and Jeff Lynne, contacted the publishers for Stay With Me, written by Sam Smith, James Napier and William Phillips, about similarities heard in the melodies of the choruses of the two compositions. Not previously familiar with the 1989 Petty/Lynne song, the writers of Stay With Me listened to I Won’t Back Down and acknowledged the similarity. Although the likeness was a complete coincidence, all involved came to an immediate and amicable agreement in which Tom Petty and Jeff Lynne are now credited as co-writers of Stay With Me along with Sam Smith, James Napier and William Phillips.

Musicologist Michael Arrington told USA Today that in comparison to other copyright infringement cases, Petty’s case against Smith was “really solid.”

“The fact that it keeps going and going: there are several phrases, and the rhythms are the same or extremely close to being the same,” Arrington said. “At some point, the similarity goes on too long.”

“Stay With Me” is nominated for both Song of the Year and Record of the Year at this year’s Grammy Awards on February 8. As noted by the Los Angeles Times, it would be pretty entertaining to see Petty and Lynne walk onstage and accept the award alongside Smith, should the song win.