Tom White, who is in his 15th season as an NFL official, was docked half his paycheck for the game. The Ravens went on to win, 44-41, in overtime.
"Players are held accountable, coaches are held accountable and we need to be held accountable," Mike Pereira, the league's supervisor of officials, told the NFL Network.
White, as head of the seven-man crew of officials, was fined because he was in control. The entire crew was downgraded in the league's rating system.
Pereira said the day after the game that referees erred by not restarting the clock after conferring over a penalty call with 58 seconds left in regulation. Seattle had the ball and led 41-38.
The clock remained at 58 seconds until the next snap, a third-and-one from the Ravens' 33-yard line that Seattle didn't convert. The Ravens used their final timeout after the play, a timeout they probably would have used if the clock were restarted before the third-down play.
If the Ravens didn't have any timeouts left, the Seahawks would have been able to run the game clock down to about five seconds before snapping the ball on fourth down. Instead, the Ravens got the ball with 39 seconds left and drove 46 yards in three plays to set up a tying 40-yard field goal by Matt Stover.