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Unlikely for public companies. Executives don't want to go to jail and given the amount that would need to be paid, it would be difficult to hide that amount. Then there is the obvious, when it is paid and the unlock keys are given, it will involve a lot of people who will realize what happened.

It is really hard to hide the fact systems are infected with ransomware then suddenly you have the decryption key? The realistic steps to go through expose it to scrutiny. The risk of getting caught and going to jail is a big deterrent to an executive.