Big Blind Ante
In the later levels of poker tournaments, an ante is introduced to further drive the action besides the incentive to enter the pot formed by the small blind and big blind.
Typically, the ante is paid by every player at the table. A lot of poker players and poker tournament organizers believe this slows down the game, especially when players argue over who has, and who hasn't paid their ante.
In tournaments operating a big blind ante, as the WSOP just announced for their high roller events, the player in the big blind pays the ante for everyone at the table. As the big blind moves every hand so does the responsibility to pay the ante.
Daniel Negreanu was the big blind in the hand, so he paid the big blind ante.