Former longtime Metallica producer Bob Rock who worked on iconic albums from “The Black Album (Metallica), Load, Reload, Garage Inc., S&M, and St. Anger has sold his rights to “The Black Album”, among other pieces of music he helmed in the studio. Hipgnosis Songs Fund, an investment and song management company, acquired a total of 43 songs from Rock, who produced Metallica’s ‘90s discography and 2003’s St. Anger.