FEC v. National Conservative PAC
FEC v. National Conservative PAC, 470 U.S. 480 (1985), was a decision by the Supreme Court of the United States striking down expenditure prohibitions of the Federal Election Campaign Act of 1971 (FECA), which regulates the fundraising and spending in political campaigns.
Source: Wikipedia — FEC v. National Conservative PAC (CC BY-SA 4.0)