Treason: noun - the crime of betraying one’s country, especially by attempting to kill or overthrow the sovereign or government.

The guy broke the law and could be charged with espionage but I think treason is rather harsh.
Let him out in a couple of years - what are punishments for? To learn by? As a deterrent? Revenge?
5 years is deterrent enough for industrial espionage, he has shown contrition and there is no charge to be vengeful against, as it was nipped in the bud by security services, as no information was passed and no one hurt.
Ignore his first request for freedom and let him out in 2 years I say.

"Deaths in the Bible. God - 2,270,365
not including the victims of Noah's flood, Sodom and Gomorrah, or the
many plagues, famines, fiery serpents, etc because no specific numbers
were given. Satan - 10."