The 5-4 decision in Citizens United vs. Federal Election Commission struck down on free-speech grounds the long-standing federal and state laws that barred corporations and unions from spending money
to elect or defeat candidates for office. The decision applied to all corporations, both for-profit firms and nonprofits.

"It means a U.S. subsidiary of a foreign corporation can now spend freely in U.S. elections," said Tara Malloy, a lawyer with the Campaign Legal Center in Washington.
Question of foreign funding of U.S. elections unsettled - latimes.com