Quicken isn't taking the loss. Berkshire Hathaway is insuring the bet, and will eat the radical majority of the loss should a win occur (minus the kicker Quicken is giving Berkshire to do it).
"Buffett said one of his insurance companies is writing the $1-billion policy in exchange for a premium, which neither he nor Quicken would disclose."
The best quote on all of this so far:
"This will be the most fun. Just imagine if there's one person left [with a perfect bracket] at the last game," Buffett said. "I will go to that final game with him or her and I’ll have a check in my pocket. ... I think we'll be rooting for different teams."
http://www.latimes.com/business/money/la-fi-mo-warren-buffet...