What was the legal status of corporations in the US before the 1870s?
Corporations were considered natural persons for the purposes of making contracts, enforcing contracts, and were given the same property rights. As Justice John Marshall said in 1830, "The great object of an incorporation is to bestow the character and properties of individuality on a collective and changing body of men."
(For reference, muon2 is referring to Providence Bank v Billings (1830)).
Reading a
gloss of this opinion, the gloss states that "corporate privilege must be expressly set forth in the charter in order to receive constitutional protection." In other words, corporations are "persons" in only a very limited sense.
The issue, then, is whether revoking 14th Amendment protections to corporations limits the rights of the persons working in them.