5 things about the NFL that football fans may not know October 4, 2019 Leave a comment There are a few things about the National Football League (NFL) that many football fans might not know. Until 2015, the NFL was classified as a non-profit for 73 years. That means the league did not pay taxes on an estimated $10 billion in annual revenue. NFL icon Tim Mara was a bookie in his early life, which at the time was a legal profession, and later founded the New York Giants. His family still owns half the team. Visit Business Insider's homepage for more stories. EDITOR'S NOTE: This video was originally published on January 16, 2016.