According to the Internal Revenue Code itself, section 501(c)(4) organizations consist of:
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.
--from 26 U.S.C. section 501(c)(4) (emphasis added).
From the Treasury regulation:
An organization is operated exclusively for the promotion of social welfare if it is primarily engaged in promoting in some way the common good and general welfare of the people of the community. An organization embraced within this section is one which is operated primarily for the purpose of bringing about civic betterments and social improvements.....
--from 26 C.F.R. § 1.501(c)(4)-1(a)(2)(i) (emphasis added).
And:
The promotion of social welfare does not include direct or indirect participation or intervention in political campaigns on behalf of or in opposition to any candidate for public office.....
--from 26 C.F.R. § 1.501(c)(4)-1(a)(2)(ii).
The Treasury regulation from which these passages are quoted was promulgated in its final form in 1960, and was amended in 1990.
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