Creation
In the 1980s, the CIA was looking for a piece of art to adorn the courtyard of the New Headquarters Building that was being constructed.
Artist Jim Sanborn was selected in November 1988 for the $250,000 commission.
The sculpture was dedicated on November 3, 1990, 4 months before the New Headquarters Building itself was finished.
Breaking of the Ciphers
In June 1999, computer scientist and amateur cryptologist James Gillogly annouced that he had broken the first 3 ciphers.
Shortly after it was revealed that David Stein, who worked for the CIA but not as a cryptanalyst, had solved the same ciphers in February 1998 but knowledge of the achievement was kept within the intelligence community.
It turned out later still that cryptanalysts working for another agency, the NSA, had solved the same portion of the text years earlier. In fact, a small team had been formed to respond to a challenge issued by CIA Deputy Director Studeman in November 1992 and had broken the ciphers by December 1st.
As far as is publicly known the last cipher, K4, has resisted every attempt to break it.
The Auction
On August 14, 2025, Jim Sanborn announced that he was putting the secret of K4 up for auction, which would close on November 20 of that year.
The twist
In September two researchers (Jarett Kobek and Richard Byrne) noticed references in the auction listing to documents donated by Sanborn to the Smithsonian’s Archives of American Art in 2023.
As they searched these documents for clues to K4, they found the scrambled plaintext of K4 itself, which had been mistakenly included by Sanborn.
The auction (2)
In an effort to protect the auction, which was due to launch the next month, Sanborn and RRAuction asked the researchers to sign an NDA in exchange for a percentage of the auction proceeds—unsuccessfully.
They also sent them cease-and-desist letters and threatened to sue for various violations.
They asked the Smithsonian to seal the documents; the institution complied and sealed them for 50 years.
As the date of the auction’s launch approached they pivoted and insisted on the fact that the auction lot included the method for creating K4, which Kobek and Byrne didn’t have. The lot was updated to include a personal walkthrough by Sanborn of the methods used to create every cipher, including K5—the overarching cipher which is supposed to connect the four others together once they have all been solved.
On November 20, the lot was sold for $962,500 to an anonymous buyer.
The aftermath
On June 12, 2026, investment firm Paradigm announced that it was the anonymous buyer of the Kryptos secret.
They have set up a verification system which can be used to check if a K4 solution is correct, for $1.