Shock jock Kyle Sandilands has unleashed on his rivals this morning with evidence of what he's calling "corporate espionage".

Sandilands, who hosts Sydney's highest-rating FM breakfast program on KIIS 106.5 with Jackie 'O' Henderson, has been teasing his "dossier" of dirt on his rivals this week, and he finally got down to it this morning, dishing on some -- surprise -- petty tactics commercial radio stations use to undermine their rivals.