The man dubbed the "Mozart of chess" has spent months using high-powered chess computers to meticulously prepare moves for his gruelling 12-game match against challenger Sergey Karjakin.
But any leak of his analysis would hand a significant advantage to Crimean-born Karjakin, the fiercely-patriotic darling of Russian president Vladimir Putin.
In an unprecedented step, Carlsen, 25, has turned to tech giant Microsoft to keep his secrets safe before the event, billed as the game’s biggest for a generation, starts on November 11.
"The element of surprise is vitally important in chess,” explained the Vibeke Hansen, from Microsoft Norway.
“Therefore, it is critical that all communication during preparation and the finals is completely secure. Preparing for a World Championship demands a lot of work, analysis and strategic sparring – and a lot of computing power.
"The last few months before a match are filled with a lot of preparation and hard work; it is crucial that no data is lost or compromised."
She said Microsoft Norway will "ensure that he has a safe training environment and secure communication and collaboration tools".
Chess champions are known to go to extraordinary lengths to keep their preparations under lock and key.
The identities of their closest advisors, known as "seconds", are routinely kept top secret as the back-up teams pore over databases of previous games trying to find a novelty or new move.
