NBC Universal says advertising inventory for the broadcast of Super Bowl XLVI is sold out, with the digital stream also being close. The broadcast will feature approx 35 minutes of national ads, with additional local and network promos. The stream of the game will have less ads. Average price for a 30sec spot was $3.5M. Last year’s Super Bowl was the most watched TV broadcast in history, with 106.5M viewers. More from AdAge.