Answers: For most businesses, everybody and you don't, respectively.
First, kudo's for a thoughtful article and a splendid topic.
The reality of the global internetwork is that data shared MAY BE data published. At least in the US the courts have issued ruling to the effect that the internet is a public place, and nothing posted, or stored there has any expectation of privacy.
This is all well an good for large companies that can muster the resources and knowledge to use dedicated end to end encryption for transmission and exchange of sensitive information. (At least they have the option. . . whether or not they do is another issue.) For most businesses and individuals, privacy is a fiction. The bizarre rulings of US courts effectively gut copyright protection.
A good read on the overall subject is Marc Goodman's, Future Crimes. He refutes the argument that I don't need privacy unless I'm doing something wrong. Information has economic value. If those who work and
A purely hypothetical example. My friend, a small local florist, does amazing work. She has a number of original designs that make up a large part of her business base. She has them marked a copyrighted on all her literature. I send one to my wife on her birthday. My wife is thrilled. So thrilled that she posts several high res images showing it from all angles on social media. A local competitor, part of a national chain, copies it an undercuts her prices. The direct result is a financial loss.
Now, the Reg is the closest to social media I come, precisely for the reasons cited in Goodman's book.
And, also because I read all the fine print in the Terms and Conditions and Privacy Policy. (More on this, perhaps, in another post in the Forum's Café) As I recall those, the end effect of my wife's posting the pictures of the copyrighted work is that under the T&C the social network now claims ownership of the picture, and the rights to do anything with it they want.
Now companies can assert any kind of asinine claims and require users to accept them. I recently heard of an instance where a well-known internet company's T&C's claimed ownership of the registering company's name.
The problem, in the US at least, is the courts often support them. A company with a several billion dollar turnover and two dozen lawyers on staff can deal with this. My local florist, and literally hundreds of millions other individuals and small business entities like her, can not. In fact, my personal experience has been that it will be virtually impossible for them to find a lawyer that has the expertise to begin to handle such a case.
It is one hell of mess.
I'll to try to post a Topic to discuss the Goodman book in the Forum. Strongly recommend everyone read the book, and if you're interested, join the discussion.