Wired previously reported that personally identifiable information wasn’t stored in Amazon’s MP3s. That doesn’t appear to be true anymore.
I saw “Music file contains unique purchase identifier” on Kanye West’s brand new My Beautiful Dark Twisted Fantasy released today for $3.99 on Amazon MP3.
The record company that supplies this song or album requires all companies that sell its downloadable music to include identifiers with the downloads. Embedded in the metadata of each purchased MP3 from this record company are a random number Amazon assigns to your order, the Amazon store name, the purchase date and time, codes that identify the album and song (the UPC and ISRC), Amazon’s digital signature, and an identifier that can be used to determine whether the audio has been modified. In addition, Amazon inserts the first part of the email address associated with your Amazon.com account, so that you know these files are unique to you. Songs that include these identifiers are marked on their product detail page on Amazon.com. These identifiers do not affect the playback experience in any way.
I think this is different than the Song ID left in the comments field of Amazon MP3s. It doesn’t appear to be available on every download available from Amazon. This is the first time I’ve ever seen it.