When the NFL was negotiating its last round of TV contracts they included in their contracts a clause that would allow them to be paid even if there isn't a 2011 season. The money had to be paid back of course but the NFL lockout is a game of leverage and access to roughly $4 billion would give the NFL major leverage.
When the NFLPA brought that money into question, Special Master Stephen Burbank ruled that it did not violate the CBA. After that, Judge David Doty overruled Burbank saying that the contracts indeed violated the CBA (back when we actually had a CBA).
Doty heard from the NFL and NFLPA this week regarding the damages. The players are hoping that $4 billion is placed into escrow and Alex Marvez of FOXSports.com reports they are seeking over $700 million in TV money as well as unspecified damages.
The hearing has concluded and it's unclear when Doty will make his ruling.