Premise: Diamond Ring was an independent Japanese professional wrestling promotion that, until 2012, was known as Kensuke Office. The promotion was founded by and is owned by puroresu legend Kensuke Sasaki, who has owned and operated it since its creation in 2005. In February 2014 the promotion ran its last card, after which Sasaki announced his retirement.
Hypothesis: Diamon Ring made the most money in Japanese professional wrestling history.