Sep. 11, 2009

Assigned A+ rating to bonds of NGK Spark Plug

Sep. 10, 2009

Assigned preliminary A+ rating to shelf of NGK Spark Plug

Feb. 26, 2009

Downgraded NGK Spark Plug to A+ and revised outlook to Negative

Jan. 16, 2008

Affirmed AA-/Stable on senior debts of NGK Spark Plug

Dec. 07, 2007

Withdrawn preliminary AA- rating on shelf of NGK Spark Plug

Jul. 20, 2007

Assigned AA- to bonds of NGK Spark Plug

Jul. 18, 2007

Assigned preliminary AA- to shelf registration of NGK Spark Plug