The information needed to decipher a secret message in a sculpture at CIA headquarters has sold at auction for nearly $1 million. RR Auction of Boston announced Friday that an archive owned by artist Jim Sanborn was sold to an anonymous bidder for $963,000. The archive includes documents and coding charts for the sculpture Kryptos, dedicated in 1990. Three of the messages have been solved, but the fourth, K4, remains unsolved. Sanborn, now 80, hopes the buyer will keep its secrets and continue engaging with followers. The auction included a private meeting with Sanborn to discuss the codes.