http://reclaimdemocracy.org/personhood/snip...
Our Bill of Rights was the result of tremendous efforts to institutionalize and protect the rights of human beings. It strengthened the premise of our Constitution: that the people are the root of all power and authority for government. This vision has made our Constitution and government a model emulated in many nations.
But corporate lawyers (acting as both attorneys and judges) subverted our Bill of Rights in the late 1800's by establishing the doctrine of "corporate personhood" -- the claim that corporations were intended to fully enjoy the legal status and protections created for human beings.
We believe that corporations are not persons and possess only the privileges we willfully grant them. Granting corporations the status of legal "persons" effectively rewrites the Constitution to serve corporate interests as though they were human interests. Ultimately, the doctrine of granting constitutional rights to corporations gives a thing illegitimate privilege and power that undermines our freedom and authority as citizens. While corporations are setting the agenda on issues in our Congress and courts, We the People are not; for we can never speak as loudly with our own voices as corporations can with the unlimited amplification of money.
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This is an excellent site with lots of recommendations for further reading about the travesty called corporate personhood. Thom Hartmann's book, "Unequal Protection" provides many examples of how corporations claim their Constitutional rights to subvert regulation.
on edit: The page below provides a timeline of personhood rights -- both natural persons & artificial persons. You can see where each entity has made gains & loses.
http://reclaimdemocracy.org/personhood/personhood_timeline.pdf