501c4 (http://www.fourmilab.ch/ustax/www/t26-A-1-F-I-501.html)
of the Internal Revenue Code reads:
- (c) List of exempt organizations
-
- Civic leagues or organizations not organized for profit but operated exclusively for the promotion of social welfare, or local associations of employees, the membership of which is limited to the employees of a designated person or persons in a particular municipality, and the net earnings of which are devoted exclusively to charitable, educational, or recreational purposes.
