In 2006, MusicIP reported that the MusicDNS database had more than 22 million fingerprints of digital audio recordings.
[4][5] In 2011, Stess sold AmpliFIND to Sony, who incorporated it into the digital music service offerings of their Gracenote division.
[8] This library implements the Open Fingerprint Architecture,[9][10] a specification developed during 2000–05 by MusicIP's previous incarnation, Predixis Corporation.
If the MusicDNS service finds an approximate match, it returns a code called a PUID (Portable Unique Identifier).
The PUID code is a short, alphanumeric string based on the universally unique identifier standard.