The FSB today said it was dropping its investigation of brothers Oleg and Igor Minin.
The FSB had said earlier this month that the men, both physicists at the State Technical University in the Siberian city of Novosibirsk, published a booklet last year that outside experts determined contained classified information "related to the development of armaments."
The case was the latest in a growing number of FSB investigations into academics over allegations of espionage, revealing state secrets, or misuse of classified information.
(AP, Interfax)