Also from the same website:
“Shioda’s complete mastery of Aikido was confirmed in 1961 when Morihei Ueshiba awarded him the degree of ninth dan for his outstanding contribution to the promotion of Japanese martial arts in general and Aikido in particular was further acknowledged by the honorary award of tenth dan by the International Martial Arts Federation in 1984”
While Ueshiba was certainly no slouch the International Martial Arts Federation also known as the Kokusai Budoin is a joke.
Why this person even mentions them on his website is beyond me.
The International Martial Arts Federation offered me rank in their organization and added that I would have to be graded. When I asked by whom the “owner” of the International Martial Arts Federation who is a Judoka said he would grade me.
I asked him if he had ever trained in Okinawan Karate, his reply was “no”.
I then asked what made him think he was qualified to grant dan ranks in an art he had never studied.
Avoid the International Martial Arts Federation like the plague. They are THE dan factory of Japan.
They shell out ranks to respectable MA people to give themselves authenticity not the other way around.