501(c)(4)s and Campaign Activity: Analysis Under Tax and Campaign Finance Laws: May 17, 2013: “The campaign activities of tax-exempt 501(c)(4) social welfare organizations continue to receive considerable attention. These groups operate with less restriction after the Supreme Court’s decision in Citizens United v. FEC, which invalidated long-standing prohibitions in the Federal Election Campaign Act (FECA) on corporations and labor unions using their general treasury funds to make independent expenditures and electioneering communications. However, even after Citizens United, 501(c)(4) groups are still
subject to regulation under FECA and the Internal Revenue Code (IRC).”

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