From an interview by Andrew Dubber with David Sanjek, “former head of archives at BMI in the US, now a professor at the University of Salford”:
1) A record that is not in circulation but only exists as an archival copy in a vault effectively doesn’t exist;
2) The archival copy in the vault may not exist either.
The interview was part of Dubber’s ongoing research at his website, Deleting Music (deletingmusic.com), which is subtitled: “How the music industry is erasing culture in the digital age.”
Original post at deletingmusic.com. More on Sanjek at salford.ac.uk.