Amazon’s push to beat Google and Apple to the punch in unveiling its new “music locker” service this week could cause the company to face a combination of new copyright challenges.

The e-commerce giant’s new cloud-based music service known as Cloud Drive, which lets users store the songs they purchase on Amazon’s servers and play them from almost anywhere, is certainly convenient. The problem is that it might not be entirely legal under copyright law, according to some people in the music industry.

At issue is whether a service that offers consumers access to music via the cloud must first acquire licenses from the music labels that control the copyrights on that music. Amazon says that it doesn’t need a license. Company spokesperson Cat Griffin tells Ars Technica that “the functionality of saving MP3s to Cloud Drive is the same as if a customer were to save their music to an external hard drive or even iTunes.”