At 9:18 of the second period in the Islanders/Penguins game, Pittsburgh requested a Coach's Challenge to review if New York was off-side prior to Anders Lee's goal.

After reviewing all available replays and consulting with the Linesman, NHL Hockey Operations staff confirmed that that the Lee tagged up in the neutral zone before Josh Bailey touched the puck in the attacking zone, rendering the play onside.Therefore the original call stands -good goal New York Islanders.
Since the Coach's Challenge did not result in the original call being overturned, the Pittsburgh Penguins forfeit their time-out.