When looking at the NFL as a business entity, we must separate its governing body from the individual teams.

From 1966 to 2015, the NFL league office was recognized as a 501 (c)(6) nonprofit organization; thus, it enjoyed tax-exempt status. Under growing pressure from consumer advocacy groups & the federal government, the NFL voluntarily gave up it's tax-exempt status in 2015. The NFL is recognized as a private trade organization.

Most NFL teams are privately owned by individuals or groups of individuals and choose the corporate form of business entity. While the NFL team can choose the corporate business form of entity, NFL teams are not allowed to be owned by corporations. The one exception to this is the Green Bay Packers franchise. They are a publicly held nonprofit corporation that is community owned through the sale of stock. The stock does not trade, pay dividends or fluctuate in value. It's simply a vehicle to distribute ownership among the locals and keep the franchise in Green Bay.

Lastly, it is relevant to point out that many of these teams were purchased decades ago before the LLC business form was ever an option.