The Supreme Court has overturned federal limitations on corporate and union campaign spending. These limitations have been in place for decades. The court has essentially cleared the playing field for anyone who wants to exercise politically free speech regarding campaigns. Corporations and unions were previously prohibited from paying for ads that specifically targeted or supported named candidates. The Court's ruling does away with that prohibition.
Writing for the majority, Justice Anthony Kennedy concluded, "We find no basis for the proposition that, in the context of political speech, the government may impose restrictions on certain disfavored speakers."
Since the ruling adds freedom to the political process, it appears to me that the Supremes got one right for a change. The Obama administration complained that the Court's decision would "make vast sums of corporate money available for overt electioneering."
The ruling does not change the current prohibitions on direct contributions to candidates, but does enable corporations and unions to pay for political ads and other kinds of campaigning.
Via ABC News