November 12, 2025
3 min reading
Final clues in the CIA mystery Kryptos Puzzle released
“Kryptos has not been solved,” said artist Jim Sanborn after posting his parting clues to the “K4” section of his sculpture puzzle.
A “proof of concept” copper plate for the Kryptos sculpture up for auction.
WASHINGTON, DC—New clues to history Kryptos A puzzle sculpture installed on CIA grounds was discovered Wednesday. Speaking from the stage of the International Spy Museum, artist Jim Sanborn, who created the cryptic puzzle, said it had not been fully deciphered, as had been claimed, and shared tantalizing clues to seek the complete solution.
Later in November, Sanborn, 79, will auction the solution to the fourth part of the sculpture, called “K4” – 79 encrypted letters beginning with “OBKR.” “K4 has not been solved or deciphered,” Sanborn said, despite the September announcement that journalists Jarett Kobek and Richard Byrne had discovered its deciphered text in the Smithsonian Institution archives. (They have since pledged that the text of the solution will not be made public.)
The artist aimed to express himself before selling ownership of the complete solution. “This is sort of my last chance to pass along information about what the new owner – or, as I call him, the Kryptos goalkeeper – will be able to say and do after his transfer,” Sanborn said.
On supporting science journalism
If you enjoy this article, please consider supporting our award-winning journalism by subscription. By purchasing a subscription, you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
Installed at CIA headquarters in 1990, Kryptos is a curved copper panel that contains letters to create four coded messages. The puzzle has long intrigued cryptographers and the public, and it gained greater fame when it was referenced on the dust jacket of Dan Brown’s novel. The Da Vinci Code. Sanborn also officially announced that a long-rumored “K5” coded message will be released when K4 is resolved. The new puzzle will be visible somewhere in a “public space,” Sanborn said. The new code will involve elements of the other puzzles and, like K4, will be 97 characters long. The two 97-letter messages will share some of the same code words at the same position.
In his speech, Sanborn advised “creativity” to anyone seeking to find the key to decrypting K4. And in an open letter to the “kryptos community,” he announced four new clues to the complete solution:
-
Two events figure in the solution: a trip by Sanborn to Egypt in 1986 and the fall of the Berlin Wall in 1989.
-
The “BERLINCLOCK” mentioned in previous K4 clues refers to the Berlin World Clock.
-
The codes inside Kryptos it’s about “delivering a message”
-
K5 is thematically linked to reading text K2, “he’s buried somewhere.”
Sanborn spoke about his work at the CIA to build the sculpture, noting that if he had tried to bury other clues on site, they would have had to be “ephemeral” to pass the scrutiny he and his colleagues faced daily during the installation.
His presentation at the International Spy Museum had the air of a mystery story throughout – he was hinting at the buried secret culmination of his enigmas. When preparing for the auction of Kryptos materials, Sanborn developed an artificial intelligence response system to automate responses to those who claim to have deciphered K4. And it will share the system with the auction winner.
The first three Kryptos the puzzles were solved in the 1990s. The first two were Vigenère ciphers, which shift each letter by a predetermined amount with each use according to a pattern revealed by their key. The solution to K3 involves a transpose code that rotates the letters in an anagram fashion. The key to deciphering the puzzle is a password that reveals the rotations. Such codes were widely used during World War II and the Cold War.
K4’s encoding method, however, remains an enigma. In his speech, Sanborn good-naturedly deflected a question of Scientific American about the mathematics of the K4 solution by joking: “Who said that was even a mathematical solution?” He later noted: “I was lucky not to understand mathematics, probably due to my ability to create the code. »
It’s time to defend science
If you enjoyed this article, I would like to ask for your support. Scientific American has been defending science and industry for 180 years, and we are currently experiencing perhaps the most critical moment in these two centuries of history.
I was a Scientific American subscriber since the age of 12, and it helped shape the way I see the world. SciAm always educates and delights me, and inspires a sense of respect for our vast and beautiful universe. I hope this is the case for you too.
If you subscribe to Scientific Americanyou help ensure our coverage centers on meaningful research and discoveries; that we have the resources to account for decisions that threaten laboratories across the United States; and that we support budding and working scientists at a time when the value of science itself too often goes unrecognized.
In exchange, you receive essential information, captivating podcasts, brilliant infographics, newsletters not to be missed, unmissable videos, stimulating games and the best writings and reports from the scientific world. You can even offer a subscription to someone.
There has never been a more important time for us to stand up and show why science matters. I hope you will support us in this mission.
