Analysis of information sources in references of the Wikipedia article "501(c) organization" in English language version.
That every corporation, joint stock company or association... shall be subject to pay annually a special excise tax with respect to the carrying on or doing business by such corporation, joint stock company or association... Provided, however, That nothing in this section contained shall apply to labor, agricultural or horticultural organizations, or to fraternal beneficiary societies, orders, or associations operating under the lodge system, and providing for the payment of life, sick, accident, and other benefits to the members of such societies, orders, or associations, and dependents of such members, nor to domestic building and loan associations, organized and operated exclusively for the mutual benefit of their members, nor to any corporation or association organized and operated exclusively for religious, charitable, or educational purposes, no part of the net income of which inures to the benefit of any private stockholder or individual.
That every corporation, joint stock company or association... shall be subject to pay annually a special excise tax with respect to the carrying on or doing business by such corporation, joint stock company or association... Provided, however, That nothing in this section contained shall apply to labor, agricultural or horticultural organizations, or to fraternal beneficiary societies, orders, or associations operating under the lodge system, and providing for the payment of life, sick, accident, and other benefits to the members of such societies, orders, or associations, and dependents of such members, nor to domestic building and loan associations, organized and operated exclusively for the mutual benefit of their members, nor to any corporation or association organized and operated exclusively for religious, charitable, or educational purposes, no part of the net income of which inures to the benefit of any private stockholder or individual.
