From MLB.com:

"It's a lot of noise; that's the bottom line," Levine said. "Gary Sheffield signed the contract, he negotiated it himself -- and took great pride negotiating it himself -- and the contract is what it is. It's noise. I really don't pay much attention to it." ...

"We picked up his option, so he's our player," Levine said. "If we choose to have him play with us, he'll play with us. If we decide to trade him, in the best interest of the Yankees, he'll be traded. Or he won't be playing baseball. It's very obvious to everybody that he doesn't have a no-trade clause, but he's trying to pretend that he does. I don't blame him for attempting to get leverage, but the truth is, he has none."