If you haven’t heard of DJ Earworm, you’ve probably heard his mixes: His “United State of Pop,”a series of massive mash-ups that turn 12 months worth of top-40 hits into a single song, take over the internet once a year like clockwork. But even with over 100 million views on Youtube and a commission to make mashups for the London Olympics, DJ Earworm has never been able to sell his music legally. Now he’s the latest artist to join Legitmix, a website that uses unique software and a loophole in copyright law to pay remixers. But what makes Legitmix legal also makes Earworm’s songs cost more than most albums.

“To put out a remix or mashup,” Legitmix founder Omid McDonald told Quartz, “you need to get licenses for both the sound recording and composition of the sampled songs. This expensive, complicated, and time consuming process makes it impossible for most remixers to legally distribute their work.”

Legitmix uses an algorithm—one that McDonald says took a year and $1 million to develop—to create a file of “digital instructions” for recreating mixes. The file is essentially what remains of the song when tracks owned by other artists are subtracted. Legitmix sells this file to its users for a dollar (taking a 30% cut and giving the rest to the remixer). If users already own the copyrighted track, they just download the Legitmix file, which then creates the mix for them on their own computer. What makes Legitmix legal is that it isn’t technically selling copyrighted material, but rather the means to recreate it (without any DJing expertise). If users don’t own the tracks used in a mix, the site lets them purchase through iTunes, making sure that the original artists make their fair cut.

Most tracks on Legitmix cost $2.29, consisting of one Legitmix file and one track from iTunes. But in addition to being its most famous remixer so far, DJ Earworm is also the most prolific sampler: His United State of Pop mix for 2012 has a whopping 25 songs by other artists in it (which adds up to $32.25 to buy it legally) and his popular SummerMash ’13 has 10, costs about $14. With no advertising except for a link to Ligitmix under its YouTube video, SummerMash has sold 700 copies, with 100 of those buyers paying for the complete $14 package. Only a small fraction of the 4500 viewers click through to the “buy” page, but that’s not bad considering that the mix is readily available for free download elsewhere.

“The existing copyright laws were not designed for the realities of today’s remix culture,” McDonald said.  “While they provide a simple way to sell cover songs without needing to negotiate with the copyright holders, no such statutory framework exists for remixing.  So most remixes are released for free online, creating a situation where neither remixer nor sampled artist benefit, with the value captured instead by ISPs, pirate sites, music blogs and streaming sites.  We hope our technology will serve as a technological bridge until the copyright laws are changed to accommodate remix.”

Sales of SummerMash over the past couple weeks are far from staggering. But the fact that there are people willing to shell out $14 for a single song bodes well for artists like Earworm—and for the future of fair, profitable remixes.

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