Someone once said, “In America the height of originality is skill in concealing origins.” Fittingly, there are ongoing arguments if Albert Einstein, radio broadcaster C.E.M. Joad or even Coco Chanel is responsible for the quote. Still, the idea seems pervasive when considering the spate of recent lawsuits claiming copyright infringement.

Currently filmmaker Matthew Fulks is suing Beyoncé on the claim that she stole several visual elements from his film “Palinoia” for her visual album “Lemonade.” Led Zeppelin faces (yet another) lawsuit concerning “Stairway to Heaven.” This time by Spirit, a band who claims Led Zepplin ripped off its song “Taurus.” Justin Bieber, Skrillex and Kanye West have all been recently sued for copyright infringement.

If history is any indicator, we may never hear of many of these suits again as they’re likely settled or thrown out of court altogether. “Music infringement claims tend to be settled early on, with financially successful defendants doling out basically extorted payoffs to potential plaintiffs rather than facing expensive, protracted and embarrassing litigation,” Charles Cronin, a music copyright specialist and lecturer at the Gould School of Law at the University of Southern California, told the New York Times last year.

But one of the latest might be more reminiscent of last year’s “Blurred Lines” legal battle, and not only because Richard Busch, the Nashville attorney who represented the Gaye family against Robin Thicke and Pharrell Williams, is representing the plaintiffs.

Here’s what you need to know:

The case

British hitmaker Ed Sheeran and co-writer Johnny McDaid of Snow Patrol face a lawsuit for allegedly copying, almost note for note, a song sung by former “The X-Factor” winner Matt Cardle. According to The Hollywood Reporter, songwriters Martin Harrington and Thomas Leonard seek $20 million on the claim that Sheeran copied music from “Amazing” for the star’s 2014 hit “Photograph,” which peaked at no. 10 on the Billboard Hot 100.

While the names Harrington and Leonard might not come with the same cachet Sheeran’s has, the songwriting duo is not new to the industry — Harrington co-wrote Kylie Minogue’s hit “Love at First Sight” as well as songs for Celine Dion, Natalie Imbruglia and Atomic Kitten, and Leonard has written songs for the Backstreet Boys, George Huff and Charice.

The lawsuit, which was filed in federal court in Los Angeles on Wednesday, states:

This is an action for willful copyright infringement in which Sheeran and McDaid, the credited writers of the international hit song “Photograph,” among others, copied, and exploited, without authorization or credit, the work of other active, professional songwriters, on a breathtaking scale, unabashedly taking credit for the work of these songwriters by claiming it to be their own. This copying is, in many instances, verbatim, note-for-note copying, makes up nearly one half of “Photograph,” and raises this case to the unusual level of strikingly similar copying. … The chorus sections of “Amazing” and the infringing “Photograph” share 39 identical notes — meaning the notes are identical in pitch, rhythmic duration, and placement in the measure.

Representatives for Sheeran have not yet commented on the lawsuit, the Independent reported early Thursday morning.

The songs

Harrison and Leonard’s “Amazing,” performed by Matt Cardle:

Ed Sheeran’s hit song “Photograph”:

What needs to be proven

There’s little question that the songs are similar. As Salon notes, both are power ballads in E flat and follow similar chord progressions. None of that, though, is particularly uncommon. (This fun video offers a great example of just how common some chord progressions are.)

The notes are undoubtedly the same in many places. The suit actually includes sheet music matching notes in the two songs:

So, is that enough to prove copyright infringement? Potentially, but not necessarily.

As the complaint itself states, “words, vocal style, vocal melody, melody and rhythm” all affect what a song is. According to Forbes, “Proof of copying is necessary but not sufficient to determine copyright infringement. There must also be a substantially similarity to the prior work … where “substantial” means substantial in degree as measured either qualitatively or quantitatively and ‘similarity’ means similar in the eyes of the ordinary member of the intended audience.”

In other words, does one song recall the other in some way? Do they “feel” the same, which was a key point in the “Blurred Lines” case in which “genre and feel” mattered more than sheet music similarity. So much more that the Gaye family was awarded $7.3 million, even though the songs didn’t share many technical similarities, the New York Times reported.

As Larry Iser, a Los Angeles intellectual property lawyer who was not involved with the case, told Billboard, “even the Gaye expert struggled to find elements in common in the lead sheets of the two songs. The two songs share more of a genre, style and feel than a note by note copy.”

It’s a knotty issue, which is likely one reason Harrington and Leonard brought in Richard Busch, the Nashville-based attorney who represented the Gaye family against Thicke and Williams.

The lawyer

In a profile in which the New York Times called him a “crusading outsider,” Busch compared himself to Al Pacino’s character — Satan disguised as a lawyer — in “The Devil’s Advocate,” who claims his success derives from others underestimating him. After all, Busch went to law school in New Orleans and settled in Nashville, Tenn., which aren’t qualifications many think of when considering a higher-powered music industry attorney.

“I’m sure Pharrell Williams and Robin Thicke said, ‘Who’s this guy from Nashville, Tenn.?’” Busch said. “They didn’t see me coming.”

But Busch isn’t completely an outsider. He might not live in the Hollywood Hills, but he has a long history of working with stars in the entertainment industry involved in intellectual property cases. In 2012, he represented Eminem’s production company in a case against Eminem’s label concerning digital rights. After he settled in the production company’s favor, its manager Joel Martin called him, “a street fighter.” Later, he won a landmark case by arguing film studios cannot sample any music whatsoever without a license.

According to Billboard, he has represented Kenny Rogers, Peter Frampton, Toto and Weird Al Yankoivch. The magazine named him one of “music’s most powerful attorneys” in 2015.

Still, many consider him an outsider — and claim that’s to his advantage.

“He’s a tough competitor,” said David M. Given of San Francisco’s Phillips, Erlewine, Given and Carlin. “But I think it’s fair to say that his outside status, if you want to call it that, has empowered him to take on institutions and players in the music business that others wouldn’t.”

Busch agreed.

“By being on the outside,” he said, “everyone who hires me knows that they get 100 percent of my loyalty.”

As for the Sheeran case, Busch told the New York Times something last year that could be seen as prophetic, though only time will tell.

“I only take on cases that I believe I can win,” he said.