The distinguishing factor of nonprofits, legally, is not that they don't take in more revenue than they pay out in expenses, it's that they don't distribute those excesses (the profits) to any individual. This is the "non distribution" clause of the corporate code that classifies nonprofit organizations - profits must be re-invested in the work of the organization, in its mission.

philanthropy.blogspot.com/2013/02/data-privacy-and-public-trust.html