Dan + Shay and Justin Bieber are among the defendants in a new lawsuit that alleges they lifted a significant portion of the structure and melody for their megahit collaboration, "10,000 Hours," from another song.

Digital Music News reports that in a new lawsuit filed on Thursday (April 21) in United States District Court in California, plaintiffs Tre Lovell and Sarah Silbert from the Lovell Firm allege that Dan Smyers, Shay Mooney, Bieber and co-writers Jason Boyd, Jessie Jo Dillon and Jordan Reynolds borrowed the verse, chorus and hook from an Asia Luckey song titled "First Time Baby Is a Holiday," which Palmer Rakes and Frank Fioravanti co-wrote in 1973.

According to the legal filing, music experts who analyzed both songs have found that the songs are far more substantially similar than the number of notes that must appear in a row to justify a claim of infringement.

"Here, in contrast, several 47-note sections of '10,000 Hours' are virtually identical to parallel sections of 'First Time.' Such a lengthy expression of largely identical musical composition is nothing less than strikingly similar. This, combined with the results of a prior art search which uncovered no compositions with anywhere near this degree of similarity pre-dating 'First Time,' makes Defendants’ theft abundantly clear," the lawsuit claims. "The musicological analysis is not only compelling but constitutes overwhelming evidence that '10,000 Hours' copied and is comprised of the most important portions of 'First Time.' In fact, without 'First Time,' '10,000 Hours' would not exist."

Compare the two songs below:

Dan + Shay released "10,000 Hours" as the lead single from the country duo's fourth studio album, Good Things, in October of 2019. The song reached No. 1 on both Billboard's Hot Country Songs and Country Airplay charts, and it also made the Top 5 in the Top 40 and Adult Contemporary charts, as well as reaching No. 4 in the all-genre Billboard Hot 100. It also became a hit all over the world, and "10,000 Hours" won a Grammy for Best Country Duo/Group Performance, as well as Favorite Country Song and Collaboration of the Year at the American Music Awards.

The suit names each of the songwriters as defendants, as well as their respective publishing companies and record companies.

"Defendants have profited considerably from their exploitation of Plaintiff’s work. Plaintiff seeks redress from Defendants’ egregious and blatant violation of Plaintiff’s intellectual property rights and seeks, among other remedies, monetary compensation and attorneys’ fees," the legal filing reads. "Plaintiff also seeks an injunction enjoining Defendants from further distributing and exploiting their infringing song, as well as requiring Defendants to take all measures to ensure that Plaintiff (and/or the songwriters) receive credit and are included in any and all honors, awards and accolades, past and future, associated with the song."

The filing asks for a jury trial. Read the complete lawsuit documents via Digital Music News online.

No trial date has been set, and none of the artists named in the suit have responded to its claims in public.

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