This is How Citizens United Dies-Feds: Mexican tycoon exploited super PACs to influence US elections

[Vox Moi]

51. Corporations are associations of individuals, therefore have speech rights under the First Amendment

That was in the majority opinion.
Hogwash!
Corporations are not merely associations of individuals.
The are entities created under law for the express purpose of doing business for profit. Corporations enjoy many privileges individuals and other types of associations cannot claim, including the right to cause economic loss to its membership for any reason or no reason at all (employee-at-will).
People employed by or who own Corporations already enjoy the right of free speech and they are free to join or create associations to further exercise that right.
Asserting that a Corporation is entitled to rights under the First Amendment is contrary to the most basic premise of democracy: that each person has an equal opportunity to be heard. A person speaking as an individual or a person speaking for an association made up of people who join that association freely (a political party or interest group) is at the heart of the democratic process.
A Corporation is most often made up of people who joined out of economic necessity. Most members have no rights of free speech within that corporation nor do they have any way to participate in the decisions as to what the political stance the Corporation might make. which is restricted to a small number of corporate officers or board members. In short, this ruling allows Corporations to gag or coerce its own membership into compliance under pain of economic loss. It allows the use corporate profits, which arise from the Corporation as a whole, to be used at the discretion of a small elite. This type of political entity is entirely contrary to the most fundamental tenets of a free society.

Bonus question for Mitt "Corporations are people" Romney:
If a corporation is a person, how can it be considered an association of individuals?
If a corporation is a person, how can it be owned?