Amazon's new Cloud Drive and Cloud Player service has drawn criticism from the music industry due to the etailer not licensing music files which customers upload.
The world's largest etailer surprised many with the launch of the cloud-based music backup and streaming service, beating rivals Google and Apple who are both set to launch similar services.
One of the delays with the launch of these services is understood to be the complex and unchartered negotiations with music labels to provide blanket licensing for music uploaded to the service which has not been purchased elsewhere, which may or may not have been pirated.
An unnamed music industry representative told Billboard.biz said of the as-yet unlaunched Google and Apple services: "If they wanted to offer a third-rate service, they would have done so already."
The music industry representative called the Amazon service "uncompelling", adding "if you want to do anything feature-rich, you have to have licenses."
However Amazon spokesperson Cat Griffin told Arstechnica that the etailer believed it did not need a licence to store music on the Cloud Drive service.
"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," said Griffin.
At least one music label said that a legal challenge was on the cards. Sony Music issued a statement saying the firm was "disappointed" with unlicensed service and that "we are keeping our legal options open."