Here is the official rule page from the NFL about balls:
http://static.nfl.com/static/content..._2013_Ball.pdf
The key line everyone is interested in is this: "The ball shall be made up of an inflated (12 1/2 to 13 1/2 pounds) urethane bladder...."
And here's part of the rule that needs to be investigated:
"available for testing by the Referee two hours and 15 minutes prior to the starting time"
Were the balls tested?
