Igor Reshetin, the chief executive of Tsniimash-Export, a producer of rockets and missiles working closely with the Russian Space Agency, was found guilty of a number of crimes, including smuggling intellectual property and misappropriating funds.
The court also upheld sentences of five to 11 years in prison for the other three defendants in the case, rejecting their appeals.
Investigators said Reshetin and his co-accused had transferred knowhow that could be used to design nuclear missiles to the China Precision Machinery Import-Export Corporation (CPMIEC), inflicting losses on Russia of 110 million rubles ($4.5 million).
Tsniimash, which was licensed by the Russian Federal Aerospace Agency in 1996, faced similar allegations in 2005, and CPMIEC has been subject to U.S. sanctions under the Iran Non-Proliferation Act since mid-2003.
Founded in 1991, Tsniimash-Export has fulfilled more than 120 contracts for aerospace companies and firms in the U.S., China and other countries.
Analysts have said Russian technology might have formed the basis of China's manned space program.