I've seen a ton of those. I hate them, not because they're insulting, but because they fill the page with garbage when I print e-mails.
How could they be legally binding?
How could they be legally binding?
They're also overly broad, often claiming copyright over quotes or even content I just sent them!
As someone else has pointed out, you'd think the mere fact that someone auto-appends these things to every email diminishes the likelihood that a court would take them seriously.
Consider also the absurdity of the sender using an inherently insecure communications channel to communicate information with a demand that the receiver keep it confidential...