Definitions by Mirabel_

soft ban

(also "soft-ban") A restriction, as in character selection or technique usage in a competitive versus game, that is never explicitly stated by the players or rulebook but still stands due to unspoken player agreement. Does not apply in prize competitions.

"Akuma is not officially banned, but there is what is called a soft ban. In other words, all top players in Japan agree not to play Akuma without there being any official enforcement of this agreement."

soft ban by Mirabel_ January 9, 2014