The NFL does not release its annual financial data, but one NFL team is a public entity: the Green Bay Packers. The Packers are the best barometer for team-by-team revenue because their financial reports must be made public. In 2013 the Packers earned $187.7 million in national revenue, which consists of its portion of NFL national television contracts, sponsorships and a portion of jersey and ticket sales—split between all the NFL teams. (The Packers had total revenue of $324 million in 2013, including local revenue sources, like increased seating and ticket sales at Lambeau Field.) If you multiply the Packers' national revenue by 32 (the total number of teams in the NFL), it comes out to a little more than $6 billion.
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All those billions flow through an organization that is complicated in structure—a structure that has attracted controversy.
The money generated by sponsorships, television deals and ticket sales—the same revenue source that is disclosed by the Green Bay Packers—is taxed through a for-profit organization owned by the 32 teams, called NFL Ventures, not the actual NFL League Office. This revenue is split between the 32 teams and players under the rules of the most recent 2011 collective bargaining agreement (CBA).
However, the National Football League is organized for tax purposes as a 501(c)(6) organization under the Internal Revenue code.
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A 501(c)(6) organization exempts taxes from "business leagues, chambers of commerce, real estate boards, boards of trade, and professional football leagues (whether or not administering a pension fund for football players), which are not organized for profit."
The NFL League Office located in Manhattan receives dues from the 32 league members, or NFL teams. These funds received from the teams are used to pay for non-revenue ventures, such as office rent and the salary of the NFL commissioner, which was $44.2 million for Commissioner Goodell in 2012 and 2013. The funds received are not federally taxed, but they also cannot be declared expenses as a deduction due to the 501(c)(6) status. These funds are taxed as income once they are passed through to staff as salary, including to the commissioner, league office employees and game officials.