According to the site,
2002,2003,2004 year
This sake seems to take top rank by a contest.
Please drink it carefully.
It is precious liquor.
He did production of this sake. http://www.nakataya.com/jizake23.htm
When this cools it and drinks it, this sake is delicious.
When you warm it and drink it, you warm it to around 40 degrees Celsius from 35 degrees Celsius, and please drink it.