"I've been asked by the consignors not to reveal their identity, however, I will say that they are family/friends related," said Darren Julien, president and CEO of Julien's Auctions.
The auction kicks off on Dec. 5 and it will include more than 1,000 items, many once owned by the "Man in Black" and his family.
The big-ticket items include the jumpsuit that Cash wore during rehearsal of his legendary performance at San Quentin State Prison in 1969; the famous photograph also from that concert that shows defiant Cash giving the middle finger to the camera; a passport from 1968; and even Cash's one time credit cards.
"The instrument can also be seen in Cash's hands for the cover photo of 'The Survivors,' a live album recorded in Germany that featured a reunion of Johnny, Carl Perkins and Jerry Lee Lewis," said Julien.
A portion of the proceeds will be donated to the MusiCares charity, which helps musicians with health or financial problems.