This is a HOT topic right now in light of the Supreme Court's recent decision in Citizens United v. Federal Election Commission. In that case, the Court held in a controversial 5-4 decision that a corporation has a right of free speech that includes the ability to spend money influencing campaigns. Polls indicate that about 80% of Americans oppose the idea that corporations should have an unlimited right to influence the political process. But the Supreme Court held otherwise in Citizens United, and for now, that is the law of the land.
So, yes, you're statement is pretty much true. Corporations are not "natural persons" but they are deemed "persons" that are entitled to certain protections under the Constitution.
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