Here:
UFC president Dana White explained to a group of reporters following this week’s UFC 130 pre-fight press conference (transcribed by MMA Junkie).
“First of all, sometimes an event becomes bigger than we anticipated it to be. Sometimes there's more money involved than we budgeted or thought could happen. What do we do? We share with them. We're not going to go, 'Hey, listen. That's your deal, buddy. You signed that deal. I don't care how big this event was,' even though that's our right to do so.